Intervention Review

You have free access to this content

Foam dressings for venous leg ulcers

  1. Susan O'Meara*,
  2. Marrissa Martyn-St James

Editorial Group: Cochrane Wounds Group

Published Online: 31 MAY 2013

Assessed as up-to-date: 25 OCT 2012

DOI: 10.1002/14651858.CD009907.pub2


How to Cite

O'Meara S, Martyn-St James M. Foam dressings for venous leg ulcers. Cochrane Database of Systematic Reviews 2013, Issue 5. Art. No.: CD009907. DOI: 10.1002/14651858.CD009907.pub2.

Author Information

  1. University of York, Department of Health Sciences, York, UK

*Susan O'Meara, Department of Health Sciences, University of York, Area 2 Seebohm Rowntree Building, Heslington, York, YO10 5DD, UK. susan.omeara@york.ac.uk.

Publication History

  1. Publication Status: Edited (no change to conclusions)
  2. Published Online: 31 MAY 2013

SEARCH

 

Summary of findings    [Explanations]

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

 
Summary of findings for the main comparison. polyurethane foam dressing compared to hydrocellular foam dressing for venous leg ulceration

polyurethane foam dressing compared to hydrocellular foam dressing for venous leg ulceration

Patient or population: patients with venous leg ulceration
Settings: All settings.
Intervention: polyurethane foam dressing
Comparison: hydrocellular foam dressing

OutcomesIllustrative comparative risks* (95% CI)Relative effect
(95% CI)
No of Participants
(studies)
Quality of the evidence
(GRADE)
Comments

Assumed riskCorresponding risk

Hydrocellular foam dressingPolyurethane foam dressing

Time to healing
Follow-up: 24 weeks
Study population1 RR 1.24
(0.91 to 1.49)2
156
(1 study)
⊕⊕⊝⊝
low3,4,5,6

617 per 1000765 per 1000
(562 to 920)

Low1

465 per 1000577 per 1000
(423 to 693)

High1

757 per 1000939 per 1000
(689 to 1000)

Proportion of participants with healed ulcers
Follow-up: 8 weeks
Study population1 RR 1.03
(0.6 to 1.78)
118
(1 study)
⊕⊕⊝⊝
low3,4,6,7

300 per 1000309 per 1000
(180 to 534)

Low1

198 per 1000204 per 1000
(119 to 352)

High1

507 per 1000522 per 1000
(304 to 902)

Proportion of participants with healed ulcers
Follow-up: 16 weeks
Study population1 RR 1.60
(0.75 to 3.42)
18
(1 study)
⊕⊕⊝⊝
low3,4,6,7

500 per 1000800 per 1000
(375 to 1000)

Low1

465 per 1000744 per 1000
(349 to 1000)

High1

757 per 10001000 per 1000
(568 to 1000)

Proportion of participants with healed ulcers
Follow-up: 24 weeks
Study population1 RR 1.08
(0.85 to 1.37)
156
(1 study)
⊕⊕⊝⊝
low3,4,5,6

617 per 1000667 per 1000
(525 to 846)

Low1

465 per 1000502 per 1000
(395 to 637)

High1

757 per 1000818 per 1000
(643 to 1000)

Mean change in wound size, with adjustment for baseline sizeSee commentSee commentNot estimable0
(0)
See commentOutcome not reported (2 RCTs reported mean change in ulcer area, with no variance estimate, and no adjustment for baseline area).<BR/>

Proportion of participants experiencing adverse events
Follow-up: 24 weeks
272 per 10008307 per 1000
(187 to 502)
RR 1.13
(0.69 to 1.85)
156
(1 study)
⊕⊕⊝⊝
low3,4,5,6

Health-related quality of lifeSee commentSee commentNot estimable0
(0)
See commentOutcome not reported.

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: Confidence interval; RR: Risk ratio;

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

 1 Note: lower risk of the outcome is less favourable (i.e. lower risk of healing) than higher risk. Estimates for baseline low and high risks of healing at 60 days (8 weeks) and 120 days (17 weeks) have been taken from a meta-analysis of RCTs evaluating different types of compression. The low risk estimate is based on a subset of participants with larger baseline ulcer area (greater than 5 cm squared). The high risk estimate is based on a subset of participants with smaller baseline ulcer surface area (5 cm squared or smaller). Most participants received a simple, low-adherent dressing plus four-layer bandage (O'Meara 2007).
2 The hazard ratio estimate presented in the RCT paper was converted to a risk ratio using a formula described in the GRADE handbook (Schünemann 2009). The baseline risk of healing for the study population is based on the proportion of patients on hydrocellular foam dressing with healed ulcers at 24 weeks.
3 RCT was at overall high risk of bias.
4 Estimate based on single RCT; unable to assess heterogeneity.
5 Number of patients recruited was lower than that estimated in the pre-specified sample size estimation.
6 Estimate based on single RCT; unable to formally assess presence of publication bias.
7 Estimate based on single, small RCT.
8 The baseline risk of adverse events is derived from the study population (proportion of patients on hydrocellular foam dressing who reported any adverse event during the 24 week trial).

 Summary of findings 2 foam dressing compared to paraffin gauze dressing for venous leg ulceration

 Summary of findings 3 foam dressing compared to hydrocapillary dressing for venous leg ulceration

 Summary of findings 4 foam dressing compared to hydrocolloid dressing for venous leg ulceration

 Summary of findings 5 foam dressing compared to knitted viscose dressing for venous leg ulceration

 

Background

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

For definitions of terminology see Glossary of terms (Appendix 1).

 

Description of the condition

Venous leg ulcers are a common and recurring type of chronic, or complex, wound. They are usually caused by venous insufficiency (impaired venous blood flow) brought about by venous hypertension. Predisposing factors for venous hypertension include history of deep vein thrombosis (DVT), thrombophlebitis, leg trauma, arthritis, obesity, pregnancy and a sedentary lifestyle. These factors can result in damage to the valves in the leg veins allowing pathological (disease-causing) two-way blood flow instead of the normal one-way movement. A related issue is diminished calf muscle pump action. Both valvular and calf-muscle pump impairment can result in reduced venous blood flow leading to venous hypertension. This causes distension of the leg veins, oedema of the lower limb and leakage of circulatory fluids from the capillaries into the surrounding tissues. This, in turn, induces irritation and increased fragility of the epidermis (the outer layer of skin) leading to ulceration (Doughty 2007). The duration of venous leg ulceration ranges from a matter of weeks to more than 10 years and some people never heal (Moffatt 1995; Ruckley 1998; Vowden 2009a). Older patient age, longer wound duration and larger ulcer surface area have been reported as independent risk factors for delayed ulcer healing (Margolis 2004; Gohel 2005).

A review of 11 venous leg ulceration prevalence studies conducted in Australia and Europe estimated point prevalence as 0.1% to 0.3% (Nelzen 2008). Surveys undertaken in the UK estimated prevalence of venous leg ulceration as 0.023% in Wandsworth, London (Moffatt 2004); 0.044% in Hull and East Yorkshire (Srinivasaiah 2007); and 0.039% in Bradford and Airedale (Vowden 2009a; Vowden 2009b). The lower estimates reported in the UK surveys relative to the worldwide literature might be explained by differences in disease management or case definition, or both. We were unable to identify contemporary prevalence data for non-western countries. The epidemiological data have consistently suggested that prevalence increases with age, and is higher among women (Margolis 2002; Graham 2003; Lorimer 2003; Moffatt 2004; Vowden 2009a).

Diagnosis of venous leg ulceration can be made according to the appearance and location of the ulcer. Clinical practice guidelines recommend the use of clinical history, physical examination, laboratory tests and haemodynamic assessment (RCN 2006; SIGN 2011a). The latter typically includes an assessment of arterial supply to the leg using the ankle-brachial pressure index (ABPI), measured using a hand-held Doppler ultrasound device. An ABPI measurement of more than 0.8 is generally used to rule out the co-existence of clinically significant peripheral arterial disease in a leg ulcer that has been diagnosed as due to venous insufficiency (Moffatt 2007).

Leg ulcers are associated with considerable cost to patients and to healthcare providers. Two systematic reviews summarised the literature on health-related quality of life in patients with leg ulcers (Persoon 2004; Herber 2007). Both included qualitative and quantitative evaluations and reported that the presence of leg ulceration was associated with pain, restriction of work and leisure activities, impaired mobility, sleep disturbance, reduced psychological well-being and social isolation.

The cost of treating an unhealed leg ulcer in the UK has been estimated to be around GBP 1300 per year at 2001 prices (Iglesias 2004). Another evaluation estimated the average cost of treating a venous leg ulcer in the UK (based on costs for material for dressing changes) as lying between EUR 814 and EUR 1994, and, in Sweden, as lying between EUR 1332 and EUR 2585 (price year 2002), with higher costs associated with larger and more chronic wounds (Ragnarson Tennvall 2005). This reflected findings from a more recent evaluation conducted in Hamburg, Germany, recruiting 502 community based adult patients with any type of leg ulcer. The total mean annual cost of illness for leg ulcers was estimated as EUR 9060 per patient (price year 2006), taking account of direct, indirect and intangible costs from a societal perspective. Direct costs included all expenses directly related to leg ulcer care (dressings, bandages, topical agents, systemic treatment, diagnostic procedures, clinician fees, in-patient treatment costs and transport); indirect costs related to loss of productivity; and intangible costs included impact on health-related quality of life. Estimates ranged from zero cost (i.e. no treatment) to EUR 44,462, with higher costs associated with arterial aetiology of the ulcer, larger wound size and no history of wound closure (Augustin 2012). In Bradford, in the UK, GBP 1.69 million was spent on dressings and compression bandages, and GBP 3.08 million on nursing time (estimates derived from resource use data for all wound types, not just venous leg ulcers) during the financial year 2006-2007 (Vowden 2009c). We were not able to identify further contemporary international cost data.

Compression therapy (bandages or stockings) is now considered to be the cornerstone of venous leg ulcer management (Moffatt 2007; O'Meara 2009). Primary wound contact dressings (i.e. dressings in direct contact with the wound bed) are usually applied underneath compression devices. A range of other interventions may be used concurrently with compression, including debriding agents (Davies 2005), vasoactive drugs (Robson 2006), fibrinolytic therapy (Robson 2006), physical therapies (Flemming 2001; Ravaghi 2006; Al-Kurdi 2008), and topical applications (Robson 2006).

 

Description of the intervention

Primary wound contact dressings are applied with the aim of aiding healing, providing comfort, controlling exudate (the fluid produced by wounds) and helping to prevent bandages and stockings from adhering to the wound bed. The ideal conditions required for wound healing in terms of dressing application have been explained as follows: maintenance of a moist wound environment without risk of maceration (excessive softening of skin because of being constantly wet); avoidance of toxic chemicals, particles or fibres in the dressing fabric; a minimal number of dressing changes; and maintenance of an optimum pH level (balanced acidity and alkalinity) (BNF 2013).

Several types of wound dressing are available and costs vary (Appendix 2). For example, there can be a six-fold difference in the UK unit price of a 9.5 cm x 9.5 cm non-adherent (knitted viscose) dressing compared with a 10 cm x 10 cm polyurethane foam dressing (BNF 2013).

Foam dressings were one of the first advanced (modern) dressings to be used in wound management and are available internationally. In the UK, foam dressings are one of a variety of advanced wound dressings that are currently available, and are used frequently, being common to many wound-care formularies. One of the purported advantages of foam dressings is their exudate handling properties, not only through absorption of exudate into the fabric of the dressing, but also via transmission through a top sheet, keeping moisture away from the wound margin (and thereby potentially reducing the risk of maceration of peri-ulcer skin). If necessary, foam dressings can be used in combination with a secondary dressing, with the latter absorbing excess exudate. It has been suggested that foam dressings can remain in place for longer than other dressing types, which provides potential to decrease the frequency of dressing changes and, therefore, reduce costs. Another suggested benefit is non-traumatic dressing removal (Sussman 2010). There is a variety of foam products on the market, and these vary in their ability to absorb exudate. Some are suitable for only lightly- to moderately-exuding wounds, whilst others have a greater fluid-handling capacity.

Several potential disadvantages of foam dressings have been noted, namely, the possibility of saturation leading to maceration of healthy peri-ulcer skin and also potential reduction in fluid-handling capacity if used beneath compression devices.

Examples of foam dressings currently available in the UK include Allevyn® Non-Adhesive (Smith and Nephew) and Biatain® Non-Adhesive (Coloplast). Appendix 2 provides a description of all wound dressings categorised by the British National Formulary (BNF 2013).

 

How the intervention might work

Findings from research based on animal models suggest that acute wounds heal more quickly when the wound surface is kept moist, so that formation of a hard scab or eschar is prevented (Winter 1963). A moist environment is also thought to provide optimal conditions for promoting autolytic debridement (the breakdown of dead cells lying on top of the wound bed), which is sometimes considered to be an important part of the healing pathway (König 2005). It is purported that foam dressings manage exudate, provide a moist wound healing environment and promote healing (BNF 2013).

 

Why it is important to do this review

Wound dressings are a key part of the treatment pathway when caring for venous leg ulcers. Most will be used in combination with compression systems, and guidelines are necessary to help make decisions regarding the value, and best use, of the available dressings. Several types of wound dressing are available and costs vary considerably, however, the evidence base to guide dressing choice is sparse. A previous Cochrane review that evaluated different wound dressings for venous leg ulcers concluded that the type of dressing applied beneath compression had not been shown to affect ulcer healing (Palfreyman 2006). The review authors concluded that there was no evidence of benefit for foam dressings compared with non-adherent dressings, nor for different types of foam dressings compared with one another.  

This review will now update part of the previous Palfreyman 2006 Cochrane review and will be one of several Cochrane reviews investigating the use of dressings in the treatment of venous leg ulcers. Each review will focus on a particular dressing type, which, in this review, will be foam dressings. These reviews will eventually be summarised in an overview of reviews (Becker 2011), which will draw together all existing Cochrane review evidence regarding the use of dressings in the treatment of venous leg ulcers.

 

Objectives

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

To determine the effects of foam dressings compared with alternative dressings, non-dressing treatments or no dressing, with or without concurrent compression therapy, on the healing of venous leg ulcers; and to determine the comparative effects of foam dressings with alternatives on health-related quality of life, costs, pain, dressing performance (management of wound exudate and ease of removal) and adverse effects.

 

Methods

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms
 

Criteria for considering studies for this review

 

Types of studies

We included randomised controlled trials (RCTs), either published or unpublished, that evaluated the effects of any type of foam dressing in the treatment of venous leg ulcers, irrespective of publication status or language. RCTs reported in abstract form only were eligible for inclusion, provided adequate information was presented in the abstract, or was available from the authors. Studies using quasi-randomisation were excluded.

 

Types of participants

RCTs recruiting people described in the primary report as having venous leg ulcers, managed in any setting, were eligible for inclusion. As the method of diagnosis of venous ulceration may vary, we accepted definitions as used in the RCTs. We included RCTs that recruited samples comprising people with venous leg ulcers and people with other types of wounds (e.g. arterial ulcers, diabetic foot ulcers) if the results for people with venous ulcers were presented separately (or separate data available from the authors), or if the majority of participants (75% or more in each arm) had leg ulcers of venous aetiology (origin).

 

Types of interventions

The primary intervention of interest was foam wound dressings. For ease of comparison we categorised dressings according to the British National Formulary (BNF 2013). We have presented generic names where possible, also providing trade names and manufacturers where available. It is important, however, to note that manufacturers and distributors of dressings may vary from country to country, and dressing names may also differ. We did not include RCTs evaluating foam dressings impregnated with antimicrobial, antiseptic or analgesic agents, as these interventions are evaluated in other Cochrane reviews (Briggs 2012; O'Meara 2010), and will be captured in the proposed overview of reviews (see Why it is important to do this review). RCTs evaluating wound dressing pads, hydrocolloid dressings, hydrogels and alginate dressings will be covered in other, separate Cochrane reviews and are included in this review only if they are comparators to foam dressings. Forthcoming, related Cochrane reviews on dressings for venous leg ulcers will, along with this review, update the review by Palfreyman 2006.

We included any RCT in which the presence or absence of a specific foam dressing was the only systematic difference between treatment groups; and in which a foam dressing was compared with other wound dressings (including alternative foam dressings), non-dressing treatments (for example, topical applications) or no dressing. We included RCTs of foam dressings, irrespective of whether compression therapy was reported as a concurrent treatment.

 

Types of outcome measures

 

Primary outcomes

The primary outcome for the review was complete wound healing.

Wound healing is measured and reported by trialists in many different ways, including time to complete wound healing, the proportion of wounds healed during follow up and rates of change of wound size. For this review we regarded RCTs that reported one or more of the following as providing the best measures of outcome in terms of relevance and rigour:

  • time to complete wound healing (correctly analysed using survival, time-to-event approaches, ideally with adjustment for relevant covariates such as baseline size);
  • the proportion of ulcers healed during follow up (frequency of complete healing);
  • and change (and rate of change) in wound size, with adjustment for baseline size.

We considered evidence from RCTs that reported mean or median time to healing without survival analysis (i.e. they regarded time to healing as a continuous measure without censoring), and those that measured and reported change or rate of change in wound size without adjustment for baseline size, as less rigorous assessments of these outcomes, and did not use data reported in this manner to populate the Summary of Findings tables (see Summary of Findings tables).

 

Secondary outcomes

The secondary outcomes for the review were:

  • rates of all reported adverse events (e.g. infection, eczema, maceration);
  • health-related quality of life (measured using a validated standardised generic questionnaire such as EQ-5D, SF-36, SF-12 or SF-6, or validated disease-specific questionnaire) preferably with follow-up estimates adjusted for baseline scores;
  • cost (including cost or cost-effectiveness estimations, as well as measurements of resource use such as number of dressing changes, dressing wear time and nurse time);
  • pain (e.g. at dressing change, between dressing changes or over the course of treatment);
  • dressing performance (exudate management and ease of removal or adherence to the wound bed).

 

Search methods for identification of studies

 

Electronic searches

In October 2012 we searched the following electronic databases for potentially relevant RCTs:

  • the Cochrane Wounds Group Specialised Register (searched 25 October 2012);
  • the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 10);
  • the Database of Abstracts of Reviews of Effects (DARE) (The Cochrane Library 2012, Issue 10);
  • the Economic Evaluation Database (The Cochrane Library 2012, Issue 10);
  • Ovid MEDLINE (1948 to October Week 3 2012);
  • Ovid MEDLINE (In-Process & Other Non-Indexed Citations, 25 October 2012);
  • Ovid EMBASE (1974 to 2012 Week 42);
  • EBSCO CINAHL (1982 to 19 October 2012).

We used the following search strategy in the Cochrane Central Register of Controlled Trials (CENTRAL):

#1 MeSH descriptor: [Occlusive Dressings] explode all trees 436
#2 foam*:ti,kw,ab 929
#3 (ActivHeal or Allevyn or Avazorb or Biatain or Copa or LyoFoam or PermaFoam or PolyMem or Suprasorb or Tegaderm or Tielle or Transobent or Trufoam or UrgoCell):ti,kw,ab 171
#4 #1 or #2 or #3 1465
#5 MeSH descriptor: [Leg Ulcer] explode all trees1064
#6 ((varicose next ulcer*) or (venous next ulcer*) or (leg next ulcer*) or (stasis next ulcer*) or (crural next ulcer*) or "ulcus cruris" or "ulcer cruris"):ti,ab,kw 1408
#7 #5 or #6 1830
#8 #4 and #7 126

The search strategies for Ovid MEDLINE, Ovid EMBASE and EBSCO CINAHL can be found in Appendix 3. We combined the Ovid MEDLINE search with the Cochrane Highly Sensitive Search Strategy for identifying randomised trials in MEDLINE: sensitivity- and precision-maximising version (2008 revision) (Lefebvre 2011). We combined the EMBASE search with the Ovid EMBASE filter developed by the UK Cochrane Centre (Lefebvre 2011). We combined the CINAHL searches with the RCT filters developed by the Scottish Intercollegiate Guidelines Network (SIGN 2011b). We did not restrict searches with respect to language or date of publication.

We searched for ongoing RCTs in the World Health Organization International Trial Registry Platform (http://www.who.int/ictrp/en/ accessed 1 August 2012) and the ISRCTN (International Standard Randomised Controlled Trial Number) register (http://www.controlled-trials.com/isrctn/ accessed 1 August 2012) using the search term 'leg ulcer'.

 

Searching other resources

We attempted to contact trialists to obtain unpublished data and information as required, along with manufacturers to request information about ongoing or as yet unpublished RCTs (for a list of manufacturers see Appendix 4). We also searched the reference lists of RCT reports identified for inclusion and of other systematic review articles. 

 

Data collection and analysis

 

Selection of studies

Two review authors independently assessed the titles and abstracts retrieved by the searches for relevance. After this initial assessment, we obtained full text copies of all RCT reports felt to be potentially relevant. Two review authors then independently checked the full papers for eligibility, with disagreements resolved by discussion, and, where required, referral to the editorial base of the Cochrane Wounds Group. We recorded all reasons for exclusion.

We have presented our study selection process as a PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flow diagram (Liberati 2009) (see Results of the search).

 

Data extraction and management

We extracted and summarised details of the eligible RCTs using a data extraction sheet. We extracted the data from RCT reports using an Excel spreadsheet designed to capture the information detailed below. Initially, we piloted the spreadsheet with a sample of eligible RCTs, to explore any issues that might arise in relation to the data extraction process. We expanded and amended the spreadsheet as necessary after the piloting process. Two review authors performed independent data extraction of all included RCTs, after which both data extractions were compared, and a final version agreed. We resolved any disagreements by discussion. If data were missing from reports we attempted to contact the trial authors to obtain the missing information. We included RCTs published as duplicate reports (parallel publications) once, using all associated reports to extract a maximal amount of information, but ensuring that data were not duplicated in the review. We extracted the following information:

  • trial authors;
  • year of publication;
  • country where RCT performed;
  • setting of care;
  • unit of investigation – participant, leg or ulcer;
  • overall sample size and methods used to estimate statistical power (relates to the target number of participants to be recruited, the clinical difference to be detected and the ability of the RCT to detect this difference);
  • participant selection criteria;
  • number of participants randomised to each treatment arm;
  • baseline characteristics of participants per treatment arm (gender, age, baseline ulcer area, ulcer duration, prevalence of co-morbidities such as diabetes, prevalence of clinically infected wounds or colonised wounds, previous history of ulceration, baseline levels of wound exudate, and participant mobility);
  • details of the dressing/treatment regimen prescribed for each arm including details of concomitant therapy, for example, compression;
  • duration of treatment;
  • duration of follow up;
  • statistical methods used for data analysis;
  • primary and secondary outcomes measured;
  • primary and secondary outcome data by treatment arm;
  • adverse effects of treatment (per treatment arm with numbers and type);
  • withdrawals (per treatment arm with numbers and reasons); and
  • source of trial funding.

 

Assessment of risk of bias in included studies

Two review authors independently assessed each included RCT report using the Cochrane Collaboration tool for assessing risk of bias (Higgins 2011a). This tool addresses specific domains, namely: sequence generation, allocation concealment, blinding of participants and personnel, blinding of outcome assessment, incomplete outcome data and selective outcome reporting (see Appendix 5 for details of the criteria on which judgements were based). For blinded outcome assessment we made separate judgements for primary and secondary outcomes. As the primary outcomes for this review (wound healing), whichever way measured, are subject to potential observer or measurement bias, blinding of outcome assessment is important. Similarly we made separate judgements for primary and secondary outcomes for the domain of incomplete outcome data. In order to assess selective outcome reporting, we sought protocols for all included RCTs. Where protocols were unavailable, we made a judgement based on congruence of information in methods and results sections of reports of RCTs. We classified RCTs as being at overall high risk of bias if they were rated as 'high' for any one of three key domains (allocation concealment, blinding of outcome assessors and completeness of outcome data). We classified RCTs as being at overall unclear risk of bias if any one of the three key domains was rated as unclear. RCTs were judged to be at overall low risk of bias only if all three key domains were rated as low risk.

We have presented our assessment of risk of bias findings using 'Risk of bias' summary figures. Figure 1 is a summary of information across all included RCTs and Figure 2 shows a cross-tabulation of each individual RCT with each risk of bias item. This display of internal validity indicates the weight the reader may give the results of each RCT.

 FigureFigure 1. Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included trials.
 FigureFigure 2. Risk of bias summary: review authors' judgements about each risk of bias item for each included trial.

 

Measures of treatment effect

We have presented a narrative overview of all included RCTs, with results grouped according to the comparator intervention. We undertook statistical pooling of outcome data on groups of RCTs considered to be sufficiently similar in terms of design and characteristics of participants, interventions and outcomes, using Cochrane RevMan software (version 5.2) (RevMan 2012). We reported estimates for dichotomous outcomes (e.g. number of ulcers healed) as risk ratios (RRs) with associated 95% confidence intervals (CI). We reported estimates for continuous data outcomes (e.g. absolute or relative change in ulcer area and healing rate) as a mean difference (MD) with 95% CI. We planned to report estimates of time to healing and plot hazard ratios where available from the included RCTs. Where hazard ratios were not reported we planned, where possible, to extrapolate these using other reported data relating to time to healing (Parmar 1998). Where RCTs reported adverse events in sufficient detail (e.g. the number of participants who experienced at least one adverse event) we analysed these as dichotomous data. Where it was unclear whether the denominator was the total number of adverse events, or the number of participants, we reported these data narratively. Where adverse events were reported as dressing-related we analysed the data separately.

 

Unit of analysis issues

We recorded whether RCT reports specified participants, limbs or ulcers as the units of allocation and analysis. In cases where multiple limbs or ulcers on the same individual were studied, we planned to note whether the trialists' analysis was appropriate (i.e. correctly taking account of highly correlated data) or inappropriate (i.e. considering outcomes for multiple ulcers on the same participant as independent). Where the number of wounds appeared to equal the number of participants, we assumed that the participant was the unit of analysis, unless otherwise stated.

 

Dealing with missing data

Missing data are a common problem in RCTs. Excluding randomised participants from the analysis or ignoring those participants lost to follow up can compromise the process of randomisation and introduce bias. Where RCTs reported dichotomous complete healing outcomes for only those participants who completed the RCT (i.e. participants withdrawing and lost to follow up were excluded from the analysis), we treated the participants who were not included in the analysis as if their wound did not heal (that is, they were included in the denominator but not the numerator for healing outcomes). Where results were reported for participants who completed the RCT without specifying the numbers that were randomised per group initially, we presented only complete case data. For other outcomes we presented data for all participants randomised, where reported; otherwise we based estimates on complete cases only.

 

Assessment of heterogeneity

We considered clinical heterogeneity (that is the degree to which RCTs appear similar in terms of participants, intervention type and duration and outcome type) and statistical heterogeneity. We assessed statistical heterogeneity using the Chi² test (P value less than 0.10 was considered to indicate statistically significant heterogeneity) in conjunction with the I² statistic (Higgins 2003). The I² statistic examines the percentage of total variation across RCTs due to heterogeneity rather than chance (Higgins 2003). We considered that I² values of 40% or less indicated a low level of heterogeneity and values of 75% or more represented very high heterogeneity (Deeks 2011).

 

Assessment of reporting biases

Reporting biases arise when the dissemination of research findings is influenced by the nature and direction of results. Publication bias is one of a number of possible causes of 'small study effects' – a tendency for estimates of the intervention effect to be more beneficial in smaller trials. Funnel plots allow a visual assessment of whether small study effects may be present in a meta-analysis. A funnel plot is a simple scatter plot of the intervention effect estimates from individual RCTs against some measure of each trial’s size or precision (Sterne 2011). We planned to present funnel plots for meta-analyses comprising 10 RCTs or more using RevMan 5.2.

 

Data synthesis

We have presented a narrative overview of the included RCTs. Where appropriate, we have presented meta-analyses of outcome data using RevMan 5.2. The decision to pool data in a meta-analysis depended upon the availability of outcome data and the assessment of between-trial heterogeneity. For comparisons where there was no apparent clinical heterogeneity and the I² value was 40% or less, we applied a fixed-effect model. Where there was no apparent clinical heterogeneity and the I² value was greater than 40%, we planned to apply a random-effects model. However, we planned not to pool data where heterogeneity was very high (I² values of 75% or above).

For the dichotomous outcomes we have presented the summary estimate as a RR with 95% confidence intervals (CI). For outcomes reported as count data (i.e. where the denominator was not the number of participants), a between-group difference with 95% CI was not estimated. Where continuous outcomes were measured in the same way across RCTs, we have presented a mean difference (MD) with 95% CI. Where variance data were not available, a mean between-group difference with 95% CI was not estimated. We planned to present a standardised mean difference (SMD) when RCTs measured the same outcome using different methods. For time-to-event data, we planned to plot (and if appropriate pool) estimates of hazard ratios and 95% CIs as they were presented in the RCT reports using the generic inverse variance method in RevMan 5.2. Where hazard ratios were not reported, and could not be extrapolated, a between-group difference with 95% CI was not estimated.

 

Summary of Findings tables

We have presented the main results of the review in Summary of Findings tables. These tables present key information concerning the quality of the evidence, the magnitude of the effects of the interventions examined, and the sum of the available data for the main outcomes (Schünemann 2011a). The Summary of Findings tables also include an overall grading of the evidence related to each of the main outcomes using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation) approach. The GRADE approach defines the quality of a body of evidence with regard to the extent to which one can be confident that an estimate of effect or association is close to the true quantity of specific interest. Quality of a body of evidence involves consideration of within-trial risk of bias (methodological quality), directness of evidence, heterogeneity, precision of effect estimates and risk of publication bias (Schünemann 2011b). We planned to present the following outcomes in the Summary of Findings tables:

  • time to complete ulcer healing where analysed using appropriate survival analysis methods;
  • proportion of ulcers completely healing during the trial period;
  • change in wound size, when adjusted for baseline size;
  • adverse events; and
  • health-related quality of life.

 

Subgroup analysis and investigation of heterogeneity

We planned to conduct subgroup analyses according to whether RCTs assessed the dressing of interest with or without the application of compression therapy. We planned to exclude RCTs in which the presence or absence of compression therapy was not clearly indicated from this subgroup analysis.

 

Sensitivity analysis

Where data permitted, we planned to undertake sensitivity analyses according to risk of bias, excluding RCTs that were judged as being at overall high or unclear risk of bias (i.e. rated as high or unclear respectively for any one of three key domains - allocation concealment, blinding of outcome assessors and completeness of outcome data). We also planned to undertake a sensitivity analysis in which we excluded RCTs that reported complete healing outcomes for only those participants who completed the RCT, and RCTs that reported results for participants who completed the RCT without specifying the numbers that were randomised per treatment group initially.

 

Results

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms
 

Description of studies

See Characteristics of included studies; Characteristics of excluded studies; Characteristics of studies awaiting classification; Characteristics of ongoing studies.

 

Results of the search

The search strategy identified 436 records in total. Of these, 256 were retrieved from electronic bibliographic databases, 174 were found from registers of ongoing trials, four were identified from examination of reference lists, and two were obtained as unpublished reports whilst requesting trial protocols for the risk of bias assessment. No references were obtained as a result of contact with wound dressing manufacturers (Appendix 4).  Eight manufacturers out of 14 contacted confirmed that there were no ongoing or recently completed RCTs of foam dressings; no replies were received from the remainder. Three hundred and fifty-five records were excluded because of irrelevance on the basis of information in titles and abstracts or details of ongoing trials.

Eighty-one full text reports were retrieved, comprising: 76 published reports; three records of ongoing trials; and two unpublished reports. Following assessment of full text reports against the review's study selection criteria, 43 full text articles were excluded that reported 30 unique studies. Reasons for exclusion were as follows:

See Characteristics of excluded studies for further details.

Twelve RCTs (reported in 32 articles) were included in the review (see next section for further details). In addition, two RCTs (reported in three articles) were classified as awaiting assessment (Jørgensen 2008; Romanelli 2008), and three RCTs (reported in three articles) were ongoing (Vas 2008; Bayer 2009; Badiavas 2011). See Characteristics of studies awaiting classification and Characteristics of ongoing studies for further details. The study selection process is shown in Figure 3.

 FigureFigure 3. Flow diagram of the study selection process

 

Included studies

We included 12 RCTs that recruited 1023 participants (see Characteristics of included studies). One trial took place entirely in North America (Weiss 1996); another jointly in North America and Europe (Vanscheidt 2004); while the remaining RCTs took place in EU countries. Six were multicentred RCTs (Callam 1992; Thomas 1997; Andersen 2002; Vanscheidt 2004; Norkus 2005; Franks 2007). The remainder were conducted at single centres. Two RCTs were of a factorial design that allowed an evaluation of two dressings and two compression bandage systems (Callam 1992; Franks 2007); and another two were described as pilot studies (Weiss 1996; Andriessen 2009). The included RCTs were reported from 1990 to 2009.

Sample sizes ranged from 12 to 159 participants. Two RCTs reported that a sample size calculation had been performed (Vanscheidt 2004; Franks 2007).

The mean age of participants ranged from 55 to 78 years. The proportion of female participants ranged from 33% to 89%. Where reported, the majority of RCTs recruited participants who were ambulatory.

With the exception of two RCTs that recruited participants with leg ulcers of various aetiologies (Andersen 2002; Norkus 2005), all participants had leg ulcers of venous aetiology. An APBI less than 0.80 was an exclusion criterion in the majority of RCTs, confirmed, where reported, using hand-held Doppler or digital photoplethysmography.

The dressing comparisons evaluated by the included RCTs were as follows:

All RCTs reported the use of compression therapy for eligible participants, with one exception, where no details were provided (Banerjee 1990). The length of treatment ranged from four weeks to twelve months. Treatment settings were mainly leg ulcer clinics, hospital outpatients clinics and the community. 

With one exception (Andriessen 2009), all RCTs reported the proportion of ulcers completely healed at the end of treatment. Time to complete ulcer healing was assessed by eight RCTs (Callam 1992; Bowszyc 1995; Weiss 1996; Andersen 2002; Charles 2002; Vanscheidt 2004; Norkus 2005; Franks 2007), and change in ulcer size or healing rate was assessed by eight RCTs (Banerjee 1990; Callam 1992; Weiss 1996; Thomas 1997; Andersen 2002; Charles 2002; Vanscheidt 2004; Andriessen 2009).

 

Risk of bias in included studies

A summary of the risk of bias assessment is presented in Figure 1 and Figure 2.

 

Allocation

 

Generation of the randomisation sequence

One RCT reported using a computer-generated programme (Andriessen 2009), and another used minimisation (Charles 2002). These two RCTs were considered to be at low risk of bias for generation of the randomisation sequence. A judgement of low risk of bias for this domain was also made for Franks 2007 following personal communication with the trial authors in connection with a separate review. The remaining nine RCTs did not describe the method used for random sequence generation clearly and were classified as being at unclear risk of bias for this domain.

 

Concealment of the allocation process

One RCT reported using sequentially-numbered, sealed, opaque envelopes (Andersen 2002), and was considered to be at low risk of bias. A judgement of low risk of bias for this domain was also made for Franks 2007 following personal communication with the RCT authors. Two RCTs reported the use of envelopes for treatment group allocation, but did not specify whether the envelopes were opaque and sequentially-numbered and, therefore, were classified as being at unclear risk of bias (Andriessen 2009; Thomas 1997). The remaining eight RCTs did not clearly describe the method of treatment group allocation and were also classified as being at unclear risk of bias for this domain.

 

Blinding

 

Blinding of participants and personnel

Two RCTs provided detail in the report that the RCT was not blinded (Weiss 1996; Andersen 2002), and one trialist provided detail via personal communication that the RCT was not blinded (Franks 2007). These RCTs were judged to be at a high risk of bias for blinding of participants and personnel. One report stated that the RCT was ‘open’ but did not provide further details regarding whether or not the participants or personnel were blinded, and was classified as having an unclear risk of bias for this domain (Thomas 1997). The remainder of the included RCT reports (eight RCTs) did not provide statements regarding blinding of participants or personnel, and were also judged to be at unclear risk of bias.

 

Blinding of outcome assessment

One RCT reported that the assessors were blinded to the treatment, and was judged to be at low risk of bias for blinded outcome assessment (Andriessen 2009). Two RCTs reported that the RCT was not blinded, and were judged to be at a high risk of bias for this domain (Weiss 1996; Andersen 2002), as was another following personal communication with the trial authors (Franks 2007). One RCT was described as ‘open’ but did not state whether the outcome assessment was blinded, and was classified as unclear risk of bias (Thomas 1997). The remainder of the included RCT reports (seven RCTs) did not provide details about blinded outcome assessment, and were also judged to be at unclear risk of bias for this domain.

 

Incomplete outcome data

One RCT reported that all randomised participants completed the RCT (Andriessen 2009), and another reported that although dropouts had occurred (reasons reported and numbers balanced across groups), analyses had been according to intention-to-treat (ITT) (Franks 2007). One RCT reported that some participants withdrew from both treatment groups, but all participants randomised were accounted for in the tabulated results (Bowszyc 1995). One RCT report did not include a statement regarding participant withdrawal, however, it appeared that all participants were included in the final analysis (Zuccarelli 1992). These RCTs were all considered to be at a low risk of attrition bias. 

Andersen 2002 reported an imbalance of participants withdrawing across groups, and that the participants who withdrew were not included in the final analysis. Banerjee 1990 did not explain why some participants, other than those reported as withdrawing, were not included at follow up. Callam 1992 reported reasons for withdrawal, that withdrawals were balanced across groups, and that the analysis was undertaken as ITT, however, the report suggested that the missing participant data was not included in the final analysis. Although all participants were included in the healing analyses (ITT) of Charles 2002, not all recruited participants were included in the analyses of secondary outcomes. These four RCTs were all judged to be at a high risk of bias for this domain.

One RCT reported the use of ITT, but did not define the ITT population and presented some outcomes that did not include all of the randomised participants (Norkus 2005). The RCT by Thomas 1997 did not provide any statement regarding participant withdrawal, and, whilst all patients randomised were accounted for in tabulated healing outcomes, not all participants were accounted for in the text that reported proportions of participants whose ulcers reduced in size. The RCT by Vanscheidt 2004 reported that 29% of all participants withdrew before 9.6 weeks, but did not report the numbers withdrawing according to their group, or state whether any participants had withdrawn after 9.6 weeks. The RCT report by Weiss 1996 suggested that all participants were included in the final analysis of healing, but it was not clear whether pain and other outcomes included all participants randomised. These four RCTs were all judged to be at an unclear risk of bias for this domain.

 

Selective reporting

Six RCTs were considered to be at low risk of bias for this domain as, although the RCT protocols were not available, all RCT outcomes described in the methods section of the report were included in the results section (Banerjee 1990; Zuccarelli 1992; Weiss 1996; Thomas 1997; Norkus 2005; Andriessen 2009). 

Two RCTs were considered to be at high risk of bias for this domain as the RCT reports included results for outcomes that were not described as being evaluated in the methods section of the report (number of weekly dressing changes, Bowszyc 1995; and adverse events, Charles 2002).

RCT protocols were provided for four of the included RCTs (Callam 1992; Andersen 2002; Vanscheidt 2004; Franks 2007). The RCT by Callam 1992 was considered to be at low risk of bias for this domain as all outcomes mentioned in the RCT protocol were presented in the RCT report. The RCT by Andersen 2002 was considered to be at unclear risk of bias as, although all RCT outcomes described in the published report were in the supplied RCT protocol, it was unclear from the published report what the primary outcome was (maceration in the protocol). A secondary outcome of ‘ability to adapt’ in the protocol (translated from Danish) was not identifiable in the published report. The RCT by Franks 2007 did not report the health-related quality of life outcomes that were pre-specified in the protocol and was classified as being at high risk of bias. The RCT by Vanscheidt 2004 was considered to be at high risk of selective reporting bias, as the published report indicated the use of scales to assess some outcomes that were not detailed in the protocol, the pre-specified outcome of patient-reported dressing leakage was not reported, and the cost of managing complications specified in the protocol was not included in the RCT report.

 

Overall risk of bias

Six of the included RCTs were considered as being at overall high risk of bias (Banerjee 1990; Callam 1992; Weiss 1996; Andersen 2002; Charles 2002; Franks 2007), as they were each rated as 'high' for one or more of three key domains (allocation concealment, blinding of outcome assessors and completeness of outcome data). The remaining six RCTs were classified as being at unclear risk of bias overall (Zuccarelli 1992; Bowszyc 1995; Thomas 1997; Vanscheidt 2004; Norkus 2005; Andriessen 2009), with three having 'unclear' ratings for all three key domains (Thomas 1997; Vanscheidt 2004; Norkus 2005). None of the RCTs was rated as having a low risk of bias overall.

 

Effects of interventions

See:  Summary of findings for the main comparison polyurethane foam dressing compared to hydrocellular foam dressing for venous leg ulceration;  Summary of findings 2 foam dressing compared to paraffin gauze dressing for venous leg ulceration;  Summary of findings 3 foam dressing compared to hydrocapillary dressing for venous leg ulceration;  Summary of findings 4 foam dressing compared to hydrocolloid dressing for venous leg ulceration;  Summary of findings 5 foam dressing compared to knitted viscose dressing for venous leg ulceration

Twelve RCTs that evaluated foam dressings were included in this review. The results are presented according to the type of comparator dressing, starting with hydrocellular foam dressings compared with polyurethane foam dressings. This is followed by comparisons of foam dressings with: paraffin gauze dressings, hydrocapillary dressings, hydrocolloid dressings, knitted viscose dressings, and protease-modulating matrix dressings. Details of primary and secondary outcome data are presented in  Table 1 and  Table 2.

 

Hydrocellular foam dressings compared with polyurethane foam dressings

Three RCTs recruiting a total of 295 participants were identified that compared a hydrocellular foam dressing with a polyurethane foam dressing (Weiss 1996; Andersen 2002; Franks 2007). 

 

Primary outcomes

 
Time to complete ulcer healing

Weiss 1996 randomised eight participants to a hydrocellular foam dressing (Allevyn) and ten to a polyurethane foam dressing (Cutinova). All participants received compression therapy in the form of graduated compression stockings. The trialists reported a mean time to healing of 6.5 weeks in the hydrocellular foam group compared with 5.6 weeks in the polyurethane foam group. No variance data or P value for the between-group difference was reported. This RCT was considered to be at overall high risk of bias as it was described as a non-blinded evaluation. This RCT was a pilot study with a small sample size.

Andersen 2002 randomised 60 participants to receive a hydrocellular foam dressing (Allevyn) and 58 to receive a polyurethane foam dressing (Biatain). Short-stretch compression bandaging was used. Participants were assessed every seven days until the ulcer was completely healed or the trial period (eight weeks) was completed. It should be noted that the median baseline ulcer duration was longer in the group receiving the hydrocellular foam dressing. The mean (SD) time to healing in the hydrocellular foam dressing group was 5.0 (1.7) weeks (n = 46) compared with 5.2 (1.9) weeks (n = 53) in the polyurethane foam dressing group. A P value for the between-group difference was not reported by the trialists. This RCT was judged to be at overall high risk of bias as the RCT was described as not blinded and participants who withdrew were not included in the final analysis.

Franks 2007 randomised 81 participants to receive a hydrocellular foam dressing (Allevyn) and 75 to receive a silicone-faced polyurethane foam dressing (Mepilex). The factorial design of the RCT also allowed evaluation of two compression systems (four-layer bandage versus short-stretch bandage). Approximately 50% of participants in each randomised dressing group were randomised to each of the two compression bandaging systems. The cumulative healing rates at 12 weeks derived from Kaplan-Meier survival curves were 47.5% in the hydrocellular foam group compared with 50.7% in the polyurethane group. The hazard ratio (95% CI) estimation for healing derived from a Cox proportional hazards model adjusted for baseline covariates (ulcer size, ulcer duration and participant mobility) did not suggest a statistically significant difference between treatment groups: 1.50 (0.86 to 2.62), P value 0.16. The hazard ratio is an expression of the hazard (chance) of an event (e.g. ulcer healing) occurring in one treatment group as a ratio of the hazard of the event occurring in the other group. These results reported by Franks 2007 can be interpreted as an absence of a statistically significant difference between the hydrocellular foam dressing group and the polyurethane foam dressing group in the rate at which ulcers healed over the course of the trial, irrespective of variations in treatment delivery or participant characteristics. This RCT was considered to be at overall high risk of bias, as the outcome assessment was not blinded.

 
Proportion of ulcers completely healed

All three RCTs reported this outcome (Weiss 1996; Andersen 2002; Franks 2007). 

In the RCT by Andersen 2002, the number of ulcers healed at eight weeks was 18/60 (30%) in the hydrocellular foam dressing group compared with 18/58 (31%) in the polyurethane foam dressing group. The between-group difference was not statistically significant (RR 1.03, 95% CI 0.60 to 1.78) ( Analysis 1.1). 

Weiss 1996 reported that the number of ulcers completely healed at 16 weeks was 8/10 (80%) in the polyurethane foam group compared with 4/8 (50%) in the hydrocellular foam group. The between-group difference was not statistically significant (RR 1.60, 95% CI 0.75 to 3.42) ( Analysis 1.1).

Franks 2007 reported that the proportion of ulcers healed at 24 weeks was 50/81 (61.7%) in the hydrocellular foam dressing group compared with 50/75 (66.7%) in the polyurethane foam dressing group. The between-group difference in was not statistically significant (RR 1.08, 95% CI 0.85 to 1.37) ( Analysis 1.1).

A pooled estimate of effect across these RCTs was not undertaken because of variation in follow up periods.

 
Change in ulcer size

Weiss 1996 reported the percentage reduction in ulcer size at week three of the 16-week RCT, but did not report the dimension (area, length/width, diameter or circumference). The percentage reduction was 27% in the hydrocellular foam group compared with 13% in the polyurethane foam group. No variance data were reported. The trialists did not report a P value for the between-group difference.

Andersen 2002 reported that the mean reduction in ulcer area at eight weeks was 3.77 cm2 in the hydrocellular foam group compared with 3.18 cm2 in the polyurethane foam group. No variance data were reported. The percentage reduction in ulcer area (read from graph) was 62% in the hydrocellular foam group compared with 64% in the polyurethane foam group. The trialists did not report a P value for the between-group differences for either the absolute or relative change. 

 

Secondary outcomes

 
Adverse events

Weiss 1996 recorded the incidence of an allergic reaction and reported that 1/8 (38%) participants in the hydrocellular foam group experienced an allergic reaction (type not specified) that necessitated withdrawal from the RCT. The RCT report contained no statement regarding adverse events with respect to the polyurethane foam group.

Andersen 2002 assessed peri-ulcer skin reactions using a verbal rating scale (VRS) and reported that 2/60 (3%) participants in the hydrocellular foam group and 3/58 (5%) participants in the polyurethane foam group experienced adverse events. These included maceration, erythema, secondary infected dermatitis, erysipelas, allergic reaction and pain at dressing change; some participants experienced more than one type of adverse event. Two out of the 60 participants in the hydrocellular foam group were hospitalised and one died; these were classified by the trialists as serious adverse events. No serious adverse events were reported in the polyurethane foam group.

Franks 2007 stated that 22/81 (27%) participants in the hydrocellular foam group reported 30 adverse events compared with 23/75 (31%) reporting 23 adverse events in the polyurethane foam group. Fifteen adverse events in each group were deemed as being possibly, or definitely, dressing-related. The trialists also reported that one participant in the hydrocellular foam group died compared with none in the polyurethane foam group. The RR estimate for the number of participants experiencing adverse events did not indicate a statistically significant difference between groups: RR 1.13 (95% CI 0.69 to 1.85),  Analysis 1.2.

Pooling of data was not undertaken because of the diversity of the nature of adverse events, methods of assessment, and reporting across the three RCTs.

 
Cost: material costs

Andersen 2002 reported that the average material costs per participant per week was 18.99 dollars in the hydrocellular foam group compared with 10.87 dollars in the polyurethane foam group (type of dollars and price year not reported). The estimation included the cost of dressings (though it was unclear whether bandages and other treatments were included), but excluded nursing time. No variance data were reported. The trialists did not report a P value for the between-group difference.

 
Cost: number of dressing changes

Andersen 2002 reported that the mean number of dressing changes per week was 3.34 in the hydrocellular foam group compared with 2.14 in the polyurethane foam group. No variance data were reported. The trialists reported a statistically significant between-group difference (P value < 0.0005).

 
Pain

Weiss 1996 reported that all participants experienced a reduction in pain and stated that the participants in the polyurethane foam group preferred the comfort of the dressing (but what they were asked to compare it to was not clear). The method of assessment was not reported, and no data by group were presented.

In the RCT by Andersen 2002, participants were asked to report ulcer pain during weekly assessments. No pain was recorded for the hydrocellular foam group during 169/319 (53%) weekly assessments compared with 226/379 (60%) weekly assessments in the polyurethane foam group. The P value for the between-group difference was not reported by the trialists.

Franks 2007 reported median scores with inter-quartile ranges at four weeks for pre- and post-dressing pain derived from a visual analogue scale (VAS) and sensory pain and affective pain from the McGill pain questionnaire. The levels of pain reduced significantly for both the VAS and McGill pain scores in both groups, however, the between-group differences at week four were not statistically significant. No variance data were reported.

 
Dressing performance: exudate management

Andersen 2002 reported that dressing absorbency, assessed by recording the incidence of leakage, was rated as excellent in 12/170 (7%) of dressing changes in the hydrocellular foam group compared with 124/163 (76%) of dressing changes in the polyurethane foam group. The trialists reported a statistically significant between-group difference (P value < 0.0005). Leakage of exudate was observed in 198/309 (64%) of weekly assessments in the hydrocellular foam group compared with 172/355 (48%) of weekly assessments in the polyurethane foam group. The trialists reported a statistically significant between-group difference (P value < 0.0005).

 

Hydrocellular foam dressings compared with polyurethane foam dressings: summary of results

Evidence from three RCTs indicated that there was no statistically significant difference between hydrocellular foam dressings and polyurethane foam dressings in the proportion of ulcers completely healed at 8, 16 or 24 weeks (Weiss 1996; Andersen 2002; Franks 2007). One of these RCTs was a pilot study with a small sample size (Weiss 1996) and all three were considered to be at overall high risk of bias.

One RCT reported an adjusted hazard ratio estimate suggesting that there was no statistically significant difference between treatment groups in terms of probability of healing over the 24-week study period (Franks 2007). Data from the same RCT indicated no statistically significant difference between groups for the proportion of participants experiencing adverse events. Insufficient data were provided for the review authors to calculate measures of treatment effect for other outcomes, however, it is possible that polyurethane foam dressings perform better than hydrocellular foam dressings for exudate handling, and that pain scores are similar for the two dressings.

 

Paraffin gauze dressings compared with foam dressings

Two RCTs were identified that compared a paraffin-impregnated gauze dressing with a hydrocellular foam dressing (Banerjee 1990; Andriessen 2009). 

 

Primary outcomes

 
Proportion of ulcers completely healed

In the RCT by Banerjee 1990, 35 participants were randomised to receive a paraffin gauze dressing (Paratulle) and 36 were randomised to receive a polyurethane foam dressing (Synthaderm). The report provided no details about the use of compression therapy. The length of treatment was 17 weeks, or until the ulcer healed. More participants allocated to the paraffin gauze dressing group had mobility problems, and more participants allocated to the foam dressing group had infected ulcers. At 17 weeks 8/35 (23%) ulcers had healed in the paraffin gauze group compared with 11/36 (31%) in the polyurethane foam group. The between-group difference was not statistically significant (RR 1.34, 95% CI 0.61 to 2.92) ( Analysis 2.1). This RCT was considered to be at overall high risk of bias, as, in addition to participants reported as withdrawing, a number of other participants appeared to be missing from the final analysis. 

 
Change in ulcer size

In one RCT, the change in median ulcer area from baseline to 17 weeks (estimated by the review authors from information provided in the RCT report) was -7.0 cm2 in the paraffin gauze group compared with -5.9 cm2 in the polyurethane foam group (Banerjee 1990). The other RCT was a three-arm pilot study allocating 12 participants to receive one of three dressings: paraffin gauze (proprietary name not reported); polyurethane foam (Suprasorb P); and protease-modulating matrix (Suprasorb C). All participants wore short-stretch high compression bandages. The length of treatment was four weeks. The trialists reported that, as this was a pilot study, the sample size was not based on statistical considerations. The mean percentage change in ulcer area (range) at four weeks was -17.2% (-31% to 4.6%) in the paraffin gauze group compared with -26.4% (-17.3% to -32%) in the polyurethane foam group. No other variance data were reported. The trialists did not report a P value for the between-group difference. The comparison between foam and protease-modulating matrix dressings was reported in a later section (Andriessen 2009).

 

Secondary outcomes

 
Adverse events

Banerjee 1990 reported that 3/35 (9%) of participants in the paraffin gauze group and 7/36 (19%) of participants in the polyurethane foam group died during the course of the RCT. Andriessen 2009 reported that no adverse events were recorded during the RCT.

 
Cost: number of dressing changes

Banerjee 1990 reported that more dressings and pads were used in the polyurethane foam group than the paraffin gauze group, but did not report data by group, or a P value for between-group differences. 

 
Cost: nursing time

Banerjee 1990 reported that the nursing time spent per patient per week was five hours 40 minutes in the polyurethane foam group compared with four hours 10 minutes in the paraffin gauze group (not reported whether these values were means or medians). The trialists reported a P value of < 0.05 for the between-group difference.

 
Pain

Banerjee 1990 assessed ulcer pain weekly on a four-point scale (details of scale not reported), reporting that the score was similar across groups with no statistically significant difference, however, no data were presented. Andriessen 2009 recorded pain at each dressing removal on a 10 cm visual analogue scale (VAS). In the paraffin gauze group participants reported either moderate (mean VAS score of 4 to 6) or severe (mean VAS score of 7 to 9) pain at dressing removal, whereas in the polyurethane foam group participants reported little or no pain (mean VAS score of 1 to 2).

 
Dressing performance: adherence to the wound bed

Andriessen 2009 reported that the paraffin gauze dressing stuck to the wound bed in 72% of the dressing changes. The number of dressing changes was not reported for the polyurethane foam group.

 

Paraffin gauze dressings compared with foam dressings: summary of results

Evidence from one RCT indicated no statistically significant between-group difference in foam dressings compared with paraffin gauze dressings in the proportion of ulcers completely healed at 17 weeks (Banerjee 1990); this RCT was considered to be at overall high risk of bias. Otherwise, data were limited and measures of treatment effect could not be estimated for other outcomes.

 

Hydrocapillary dressings compared with foam dressings

We identified one RCT that compared a hydrocapillary dressing with a foam dressing (Norkus 2005).  Hydrocapillary dressings are designed to act as a wick so that exudate is drawn away from the wound surface. The dressing evaluated by Norkus 2005 (Alione adhesive, Coloplast) comprises a hydrocapillary pad surrounded by a hydrocolloid adhesive, which exposes a non-adherent ulcer contact layer, covered by a water-resistant, bacteria-proof, semipermeable top film (Morris 2003).

 

Primary outcomes

 
Time to complete ulcer healing

Norkus 2005 randomised 49 participants to receive a hydrocapillary dressing (Alione) and 48 participants to receive two polyurethane foam dressings sequentially: one at the start of the RCT (Tielle plus) followed by the other (Tielle) when dressing changes were required less frequently. Thirty-six of the 49 participants receiving the hydrocapillary dressing (73%) and 32 of the 48 participants receiving the foam dressings (67%) received compression therapy during the RCT (type not reported). Ulcers were treated until they healed, or for a maximum of 12 months. The trialists reported that no significant differences were found between the two treatment groups for time to healing, but did not present data by group or a P value for the between-group difference, and the analysis method was unclear.

 
Proportion of ulcers completely healed

Norkus 2005 reported that 25/49 (51%) ulcers had healed at 12 months in the hydrocapillary dressing group compared with 19/48 (40%) ulcers in the polyurethane foam group. The between-group difference was not statistically significant (RR 0.78, 95% CI 0.50 to 1.21) ( Analysis 3.1). The sample comprised participants with ulcers of venous, mixed or other aetiology and wounds with medium and high levels of wound exudate. Participants receiving the hydrocapillary dressing had larger and more chronic ulcers at baseline compared with those in the polyurethane foam group (median values provided). 

 

Secondary outcomes

 
Adverse events

In the RCT by Norkus 2005, research nurses assessed adverse events (odour, maceration, leakage, erythema and eczema) on a four-point scale (none, mild, moderate or severe). In the hydrocapillary dressing group 8/49 (16%) experienced adverse events (four were defined as related to the dressing: two ulcer infections and two skin reactions; however, the remaining four participants’ adverse events were not described), compared with 11/48 (23%) in the polyurethane foam group (seven were defined as related to the dressing: two ulcer infections, three eczema, one allergic reaction, and one peri-ulceration). The between-group difference was not statistically significant (RR 1.40, 95% CI 0.62 to 3.18) ( Analysis 3.2). All participants experiencing these adverse events withdrew from the RCT.

Five out of 49 participants (10%) in the hydrocapillary dressing group and 4/48 (8%) participants in the polyurethane foam group developed clinical signs of wound infection (all withdrew), but it was unclear whether any of the participants developing wound infection were amongst those withdrawing due to other adverse events. The trialists reported that one in three participants experienced some degree of maceration during the RCT, that severe maceration was only reported in the polyurethane foam group (5%), but that there were no significant between-group differences in maceration, but did not report further data or P values. The trialists reported that there were 24 (1.7%) occurrences of severe erythema in the hydrocapillary dressing group compared with 45 (3.3%) in the polyurethane foam group, however, it was unclear whether these occurrences referred to dressing changes or something else, as the denominator was not reported. The trialists reported no significant between-group difference.

 
Health related quality of life

Norkus 2005 assessed health related quality of life at the start and the end of the RCT using the WHO-5 Well-being Index. Responses to five questions were scaled from 0 to 5 and the total multiplied by four to give a maximum 100 value (the higher the score, the better the participant’s well being). At baseline, the median scores were 60 for the hydrocapillary dressing group and 48 in the polyurethane foam group; both groups achieved a median score of 68 at 12 months. The trialists reported that there were no significant differences in the initial or final values between-groups (P value not reported).

 
Cost: wear time

Norkus 2005 reported that the estimated mean wear time was 3.2 days for both dressing groups, however, no other data were presented for this outcome.

 
Pain

In the RCT by Norkus 2005 wound pain at dressing removal, and at assessment visits between dressing changes, was reported by participants on a four-point scale (none, mild, moderate or severe). There was no significant difference in the incidence of wound pain between the two groups, however, data by group and P-values were not reported

 
Dressing performance: exudate management and adherence to the wound bed

In the RCT by Norkus 2005 dressing absorption was measured on a three-point scale (good, moderate or poor). The RCT personnel were asked to estimate additional wear time based on saturation of the dressing. Adherence of the dressing to the wound bed was also assessed. The trialists reported that no significant differences in the incidence of little to moderate and severe leakage at dressing change were found between the two treatment groups, but that there was a significant difference in favour of the hydrocapillary dressing in the number dressing changes in which the dressing adhered to the wound. There was a discrepancy in the RCT report, however, regarding the denominator (the number of dressing changes) for these two outcomes, and it was unclear what the total number of dressing changes should have been in the RCT. 

 

Hydrocapillary dressings compared with foam dressings: summary of results

Evidence from one RCT indicated that there was no statistically significant difference between foam dressings and hydrocapillary dressings in the proportion of ulcers completely healed at 12 months (Norkus 2005). This RCT was considered to have an overall unclear risk of bias.

Evidence from the same RCT indicated that there was no statistically significant difference between foam dressings and hydrocapillary dressings in the number of people who experienced adverse events (Norkus 2005). Insufficient data were available to estimate treatment effects for other outcomes.

 

Hydrocolloid dressings compared with foam dressings

We identified five RCTs that compared hydrocolloid dressings with foam dressings (Zuccarelli 1992; Bowszyc 1995; Thomas 1997; Charles 2002; Vanscheidt 2004).

 

Primary outcomes

 
Time to complete ulcer healing

Time to complete ulcer healing was reported in three RCTs that compared a hydrocolloid dressing with a foam dressing (Bowszyc 1995; Charles 2002; Vanscheidt 2004).

Bowszyc 1995 randomised 40 participants to a hydrocolloid dressing and 40 participants to a polyurethane foam dressing. A high-compression elastic bandage was used with both dressings. The length of treatment was 16 weeks, or until the ulcer had healed. The trialists reported that the time to healing was 10.50 weeks in the foam group, compared with 9.34 weeks in the hydrocolloid group. The trial report did not state whether these values were means or medians. The trialists reported a P value of 0.35 for the between-group difference. This RCT was considered to be at overall unclear risk of bias.

The RCT by Charles 2002 was a three-armed RCT with 31 participants randomised to receive one hydrocolloid dressing (Granuflex), 29 participants randomised to receive another hydrocolloid dressing (Comfeel), and 31 who were randomised to a polyurethane foam dressing. All participants received short-stretch compression bandaging. Length of treatment was 12 weeks, or until the ulcer healed. The trialists reported that the mean time to healing was 7.5 weeks and 6.0 weeks respectively in the two hydrocolloid groups, compared with 7.0 weeks in the polyurethane foam group. The trialists did not report the P value for between-group difference, nor variance data. This RCT was considered to be at an overall high risk of bias.

Vanscheidt 2004 randomised 55 participants to receive a hydrocolloid dressing and 52 participants to receive a hydrocellular foam dressing. All participants received a high-compression elastic bandage. Length of treatment was 12 weeks, or until healing of the ulcer occurred. The mean (SD) time to healing was reported as 66.0 (3.4) days in the hydrocolloid group compared with 72.6 (3.1) days in the foam dressing group; trialists reported a P value of 0.47 for the between-group difference. This RCT was considered as being at unclear risk of bias overall.

 
Proportion of ulcers completely healed

Three of the RCTs evaluating hydrocolloid dressings compared with foam dressings reported number of ulcers healed at 12 weeks (Zuccarelli 1992; Charles 2002; Vanscheidt 2004).

Zuccarelli 1992 randomised 19 participants to receive a hydrocolloid dressing and 19 to receive a hydrocellular foam dressing. Compression therapy was in the form of a two-layer system. This first layer was kept in place, whereas the second layer was removed by the participant before going to bed and re-applied before getting up in the morning. The length of treatment was 12 weeks. At the end of the 12 weeks 9/19 (47%) ulcers had healed in both the hydrocolloid dressing group and the hydrocellular foam dressing group. 

Charles 2002 reported that 17/29 (59%) ulcers in the Comfeel hydrocolloid dressing group and 17/31 (55%) in the Granuflex hydrocolloid dressing group had healed at 12 weeks, compared with 18/31 (58%) ulcers in the polyurethane foam group.

The number of ulcers that healed at 12 weeks in the hydrocolloid group in the RCT by Vanscheidt 2004 was 20/55 (36%) compared with 20/52 (38%) in the hydrocellular foam group. 

Thomas 1997 randomised 50 participants to receive a hydrocolloid dressing and 50 to receive a polyurethane foam dressing. All participants received compression consisting of orthopaedic padding plus a high compression elastic bandage. The number of ulcers healed at 13 weeks in the hydrocolloid dressing group was 19/50 (38%) compared with 17/50 (34%) in the polyurethane foam group.

One RCT comparing a hydrocolloid dressing with a foam dressing reported the number of legs healed at 16 weeks (Bowszyc 1995). Bowszyc 1995 reported that 24/41 (59%) legs had healed at 16 weeks in the group receiving the hydrocolloid dressing compared with 24/41 (59%) legs in the group receiving the polyurethane foam dressing. The trialists reported that two of the 80 participants who were randomised had bilateral leg ulcers (one in each group), however, they did not report how many participants in each of the two groups had healed at 16 weeks.

We compared each of the hydrocolloid dressings evaluated by Charles 2002 in separate pooled analyses. The pooled estimates for the between-group difference in complete ulcer healing from 12 to 16 weeks across the five RCTs were not statistically significant (including the Charles 2002 Comfeel group, RR 0.99, 95% CI 0.80 to 1.22; including the Charles 2002 Granuflex group, RR 1.00, 95% CI 0.81 to 1.24) ( Analysis 4.1). Clinical advice was sought as to whether the two hydrocolloid dressings evaluated by Charles 2002 were similar enough to combine into a single treatment group for analysis (the method is detailed in the Cochrane Handbook Chapter 16.5 Higgins 2011b); this was confirmed as being appropriate. The pooled estimate for the between-group difference across the five RCTs was not statistically significant (RR 1.00, 95% CI 0.81 to 1.22) ( Analysis 4.1) (Figure 4). There was no evidence of statistically significant heterogeneity, the Chi2 P value being 0.99 and I2 estimation 0% for all three meta-analyses.

 FigureFigure 4. Forest plot of comparison: 4 Hydrocolloid compared with foam, outcome: 4.1 Proportion of ulcers completely healed at 12 to 16 weeks.

Change in ulcer size

Two RCTs reported the mean percentage change in ulcer area at final follow up (Thomas 1997; Charles 2002). Thomas 1997 presented mean change estimates at 13 weeks of -78% for the group receiving the hydrocolloid dressing and -88% for those allocated foam (read from figure). Reviewer-extrapolated estimates from Charles 2002 at 12 weeks were as follows: hydrocolloid (Comfeel) -82.1%; hydrocolloid (Granuflex) -83.6%; and foam dressing -67.3%. Both RCT reports indicated that differences between groups were not statistically significant, but no P values were provided.

 
Healing rate

Two RCTs mentioned undertaking assessment of healing rates (Zuccarelli 1992; Vanscheidt 2004). One presented only minimal information (Zuccarelli 1992), and reported that the mean ulcer size in both groups reduced steadily throughout the RCT, but no statistically significant between-group difference was observed (P value 0.86). No rate of healing data by group were reported. Data from the second RCT indicated similar median rates of healing for hydrocolloid and foam dressings, respective values being -0.41 cm2/week and -0.43 cm2/week. The respective values for median percentage healing rates per week were -7.3% and -6.1%. The trial authors reported P values of 0.13 and 0.27 respectively, for the between-group differences (Vanscheidt 2004).

 

Secondary outcomes

 
Adverse events

Zuccarelli 1992 did not report how adverse events were assessed, but reported that 2/19 (11%) participants in the hydrocolloid group experienced an allergic reaction and an intolerance in the peri-ulcer skin area in the form of blisters, whereas no unwanted side effects were reported in the hydrocellular foam group.

Bowszyc 1995 reported that complications of secondary infection and maceration occurred, and that there were eight cases of streptococcal cellulitis that required antibiotic treatment (two participants withdrew because of this). Whilst the trialists reported that the same number of participants were affected in each group, they did not report the number of participants experiencing adverse events by treatment group. Furthermore, they did not describe the method of assessment of adverse events and it was unclear whether adverse events other than maceration or cellulitis had occurred.

Thomas 1997 reported that 7/99 (7%) participants in the hydrocolloid group and 10/100 (10%) in the foam group experienced adverse events related to the adhesive nature of the dressing such as minor trauma or erythema (skin redness); this report related to the overall sample of participants with leg ulcers and pressure ulcers and was not broken down by wound type. Additional adverse events noted by the trialists included maceration, bleeding from the wound area and excessive granulation; of those with leg ulcers, these affected six, one and three participants respectively in the hydrocolloid group, and none in the foam group.

The RCT by Charles 2002 did not describe how, or which, adverse events were assessed, but reported that no serious dressing-related adverse events were observed during the RCT.

Vanscheidt 2004 recorded dressing-related adverse events and severe adverse events deemed unrelated to the dressing, together with descriptions. In the hydrocolloid group 13/55 (24%) participants experienced one or more possible dressing-related adverse event (19 events in total) compared with 15/52 (29%) participants in the hydrocellular foam group who experienced 18 possible dressing-related events. The between-group difference in participants experiencing adverse events was not statistically significant (RR 1.22, 95% CI 0.64 to 2.31) ( Analysis 4.2). The trialists also reported on the occurrence of common adverse events (e.g. maceration, new wound development in different location, and non-specific wound events), however, there were discrepancies between the numbers reported in the primary and secondary references. The trialists reported no statistically significant between-group difference (P value 1.00), but it was not clear from the report if the difference referred to the number of participants with adverse events or the difference between the total number of adverse events in each group.

The adverse events assessment and reporting across these RCTs was considered too diverse for statistical pooling of data.

 
Pain

Zuccarelli 1992 evaluated pain using a numeric scale with lower scores representing less pain. Methods for collecting these data were not described. Data were presented graphically, using a range from 1.3 to 2.7 (full range of scores not stated). Reading from the graph, the mean pain score at week 12 was 1.5 in the group receiving the hydrocolloid dressing compared with 1.7 in the group receiving the hydrocellular foam dressing. No variance data were reported. The respective changes in mean scores from baseline (calculated from graph by review authors) were -0.8 and -0.9. The trialists reported that during the RCT there was a significant pain reduction in both dressing groups (P value 0.005) but that the between-group difference was not statistically significant (P value 0.52).

Bowszyc 1995 assessed ulcer pain at dressing removal on a scale of 1 to 4 (1 = very painful and 4 = no pain) at the end of the RCT. The trialists reported a mean pain score (SD) of 3.63 (0.83) in the group receiving the hydrocolloid dressing compared with a mean score of 3.72 (0.55) in the group receiving the polyurethane foam dressing. The trialists reported that the between-group difference was not statistically significant (P value not reported). The mean change in scores from baseline with variance estimate was not reported.

Charles 2002 reported ulcer-associated pain using a 10-point visual analogue scale with lower scores indicating less pain. The mean score at the week 12 follow up was 0.64 in the hydrocolloid Comfeel dressing group (n = 28), 0.15 in the hydrocolloid Granuflex dressing group (n = 27), and 0.50 in the polyurethane foam group (n = 30). No variance data were reported. The changes in mean scores from baseline (calculated by review authors) were -3.19, -3.66 and -4.27 respectively. The trialists reported that between-group differences in pain prevalence and severity were not statistically significant at any point in the RCT (P value not reported).

In the RCT by Vanscheidt 2004, the number of participants with a reduction in pain, no effect on pain, uncertain effect, unable to respond/no response, increased pain, and those with missing data were reported for the final assessment (data were collected using the Johns Hopkins Pain Rating Instrument). The trialists reported that there were no statistically significant between-group differences (P value 0.10 for overall effect of dressing on participant-reported ulcer pain).

Due to the varied assessment methods and outcome reporting of pain assessment in these RCTs, a between-group difference in pain with 95% confidence intervals within or across these RCTs was not estimated. 

 
Cost: dressing changes

Zuccarelli 1992 reported the mean number of dressing changes over the 12 weeks of treatment as being 26.9 in the hydrocolloid group compared with 19.5 in the hydrocellular foam dressing group. The trialists did not report variance data, but did report that the between-group difference was not statistically significant (P value 0.14). 

Bowszyc 1995 reported the UK Drug Tariff price per dressing (at October 1993) as GBP 2.08 for a 10 cm x 10 cm piece of the hydrocolloid dressing compared with GBP 0.92 for a 10 cm x 10 cm piece of the polyurethane foam dressing. The reported mean number of dressing changes per week in the first month was 1.5 in the hydrocolloid group compared with 1.6 in the foam group. The trialists reported no variance data nor a statistically significant between-group difference (P value 0.49). 

The mean (SD) number of dressing changes per week in the RCT by Vanscheidt 2004 was 11.4 (6.5) in the group receiving the hydrocolloid dressing compared with 10.1 (6.3) in the group receiving the hydrocellular foam dressing. The trialists reported that there was no statistically significant between-group difference in this dressing performance outcome, however, the number of participants in each treatment group at follow up was not reported. 

We could not estimate between-group differences in the number of dressing changes with 95% confidence intervals for foam dressings compared with hydrocolloid dressings from these RCTs. 

 
Cost: wear time

Thomas 1997 reported that the mean time that the original dressing was in place prior to the first change was 2.7 days in the group receiving the hydrocolloid dressing compared with 2.8 days in the group receiving the polyurethane foam dressing. The trialists reported no variance data, nor the P value for between-group difference.

Vanscheidt 2004 reported that the mean (SD) wear time was 5.6 (1.3) days in the hydrocolloid group compared with 5.6 (1.2) days in the hydrocellular foam group. The trialists reported that there was no statistically significant between-group difference in this outcome, however, they did not report the number of participants in each treatment group at follow up.

 
Dressing performance: exudate management

Thomas 1997 reported that 27/50 (54%) of participants in the hydrocolloid group had dressings removed at the first dressing change due to leakage compared with 7/50 (14%) in the polyurethane foam group. The trialists reported that the between-group difference was statistically significant (P value < 0.0001).

In the RCT by Vanscheidt 2004, the exudate-handling property of the dressing was reported in terms of the number of dressing changes where no exudate, minimal exudate (i.e. less than 25% of dressing saturated), moderate exudate (25% to 75% of dressing saturated), or considerable exudate (more than 75% of dressing saturated) was observed. The proportion of dressing changes in each category appeared similar between groups (approximately 8%, 35%, 38% and 19% respectively), however, the trialists did not report a P value for the between-group differences. 

 
Ease of dressing removal/adherence to the wound bed

The RCT by Bowszyc 1995, assessed nurse-rated ease of dressing removal using an 11-point scale (0 = easy to remove, 11 = difficult to remove). The mean (SD) score in the hydrocolloid group was 1.42 (0.54) compared with 1.15 (0.42) in the polyurethane foam group. The trialists reported a P value of 0.016 for the between-group difference.

Thomas 1997 reported that in both treatment groups, dressing removal was rated by nurses as 'easy' in the majority of cases at the first dressing change, however, no data by group were presented.

In the three-arm RCT by Charles 2002, the foam dressing was reported to be significantly easier to remove compared with the two hydrocolloid dressings at six weeks and at the last dressing change (P value 0.021 and P value 0.037 respectively for the two time points), however, it was unclear how these P values related to the between-group comparisons, given that the trialists would have been considering three comparisons at each time point. No between-group difference with 95% confidence intervals could be estimated for this RCT.

Vanscheidt 2004 assessed participant-rated ease of dressing removal and non-traumatic dressing removal on a five-point scale (1 = excellent, 2 = very good, 3 = good, 4 = fair, 5 = poor) at the final evaluation. The proportions of participants reporting dressing changes in each of the five categories for each outcome by treatment group were presented graphically, however, the denominator (number of participants in each treatment group) was not presented. The trialists reported a between-group difference of P value 0.19 for ease of removal and P value 0.07 for non-traumatic dressing removal. No between-group differences with 95% confidence intervals could be estimated from this RCT.

 

Hydrocolloid dressings compared with foam dressings: summary of results

Pooled evidence from five RCTs indicated no statistically significant difference between hydrocolloid dressings and foam dressings in the proportion of ulcers completely healed from 12 to 16 weeks (Zuccarelli 1992; Bowszyc 1995; Thomas 1997; Charles 2002; Vanscheidt 2004). One of these RCTs was considered to be at overall high risk of bias (Charles 2002), whilst the others were judged as unclear.

Evidence from one RCT indicated no statistically significant between-group difference in the number of participants experiencing dressing-related adverse events. Insufficient data were provided to estimate measures of treatment effect for other outcomes, however, it is possible that the foam dressing was better than hydrocolloid for exudate handling and ease of removal.

 

Knitted viscose dressings compared with foam dressings

We identified one RCT that compared a knitted viscose dressing with a hydrocellular polyurethane foam dressing (Callam 1992). This RCT had a factorial design in which participants were randomised to one of two compression bandage systems as well as to one of two dressings. One of the compression systems consisted of orthopaedic padding, a high-compression elastic bandage and a graduated compression tubular bandage; the other comprised orthopaedic padding, a short-stretch crepe bandage, and a short-stretch cohesive bandage. Sixty-six participants were randomised to receive the knitted viscose dressing and 66 to receive the foam dressing. There was no statistically significant interaction between dressings and bandages (P value 0.87). The length of treatment was 12 weeks, or until the ulcer healed, whichever occurred sooner. 

 

Primary outcomes

Time to healing

Callam 1992 reported no significant difference between groups from a Cox regression model adjusted for baseline ulcer size (P value 0.08 but no hazard ratio estimate provided).

 
Proportion of ulcers completely healed

At the end of 12 weeks of treatment Callam 1992 reported that 23/66 (35%) of ulcers had healed in the knitted viscose group compared with 31/66 (47%) in the hydrocellular foam group. The between-group difference was not statistically significant (RR 1.35, 95% CI 0.89 to 2.05) ( Analysis 5.1). The trialists considered participants who withdrew from treatment as failures of treatment rather than lost to follow up. This RCT was at overall high risk of bias. 

 
Change in ulcer size

Callam 1992 reported a categorical analysis for percentage change in ulcer area from baseline to 12 weeks or participant withdrawal. Seven categories were used: more than 100% increase, 50% to 100% increase, 0% to 50% increase, 0% to 50% decrease, 50% to 100% decrease, healed and not known; data were presented in a figure. Initial or final ulcer tracings were not available for three participants, and these were excluded from the analysis. A P value of 0.051 was reported by the trialists for the overall between-group difference in ulcer area reduction.

 

Secondary outcomes

 
Adverse events

Callam 1992 reported that there were no cases of adverse reactions in the knitted viscose dressing group and that 2/66 (2%) of the hydrocellular foam group experienced local skin reactions. The between-group difference was not statistically significant (RR 5.00, 95% CI 0.24 to 102.19) ( Analysis 5.2).

 
Pain

Callam 1992 assessed the number of participants experiencing pain at 0%, 1% to 25%, 26% to 50%, 51% to 75%, 76% to 99%, and 100% of clinic visits. The trialists reported P value 0.01 in favour of the foam dressing for the between-group difference in patients experiencing pain at all (100%) clinic visits.

 

Knitted viscose dressings compared with foam dressings: summary of results

Evidence from one RCT suggested no statistically significant difference between knitted viscose dressings and foam dressings in the proportion of ulcers completely healed at 12 weeks (Callam 1992). This RCT was considered to be at overall high risk of bias. Data from the same RCT indicated no statistically significant between-group difference in the number of participants who experienced adverse events during treatment. Insufficient data were available to estimate measures of treatment effect for other outcomes, however, it is possible that the foam dressing is associated with less pain than the knitted viscose dressing.

 

Protease-modulating matrix dressing compared with foam dressing

We identified one three-armed RCT that compared a protease-modulating dressing, a paraffin gauze dressing and a foam dressing (Andriessen 2009). The comparison between the paraffin gauze and foam dressings has been described earlier.

 

Primary outcomes

 
Change in ulcer size

Andriessen 2009 reported that the mean percentage change in ulcer area (range) at four weeks was -31.8% (-28 to -34%) in the protease-modulating matrix group compared with -26.4% (-17.3 to -32%) in the polyurethane foam group. The trialists did not report a P value for the between-group differences. No other variance data were reported. A mean between-group difference with 95% CI could not be estimated for this outcome.

 

Secondary outcomes

 
Adverse events

Andriessen 2009 recorded the severity and timing of any adverse event and reported that no adverse events were observed during the RCT.

 
Pain

Using data generated from a 10-point VAS (with lower scores representing less pain), Andriessen 2009 reported that participants experienced little or no pain (classified from a mean VAS score of 1 to 2) in both groups. 

 
Dressing performance: adherence to the wound bed

Andriessen 2009 reported that the paraffin gauze dressing stuck to the wound bed in 72% of the dressing changes (total number of dressing changes not provided), but there was no report of this outcome for the foam or protease-modulating dressing groups.

 

Protease-modulating matrix dressings compared with foam dressings: summary of results

A single RCT reported this comparison (Andriessen 2009); available data were very limited and therefore inconclusive.

 

Summary of Findings tables

We have included a Summary of Findings table for the following treatment comparisons; these provide a concise overview and synthesis of the volume and quality of available evidence.

There is no Summary of Findings table for foam compared with protease-modulating matrix dressings because only limited data were reported in the single RCT evaluating this comparison (Andriessen 2009).

The Summary of Findings tables indicate that, where evidence is available, it is generally of low quality. The exception to this was for the outcome of complete healing (at 12 to 16 weeks) for the comparison of foam and hydrocolloid dressings, where the evidence was of moderate quality. Overall, the Summary of Findings tables indicated that there is no evidence of a benefit of using foam dressings compared with alternative dressings for treating venous leg ulcers.

 

Discussion

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

The purpose of this review was to determine the effects of foam dressings compared with alternatives on the healing of venous leg ulcers. In addition, we considered the effects of these dressing on: adverse events, health-related quality of life, costs, pain, and dressing performance (management of wound exudate and ease of removal).

 

Summary of main results

Twelve RCTs were included in this review. Three compared two types of foam dressings (Weiss 1996; Andersen 2002; Franks 2007), whilst the others involved comparison between foam and other types of dressings. The comparator dressings were: paraffin gauze (Banerjee 1990; Andriessen 2009); protease-modulating matrix (Andriessen 2009); hydrocapillary (Norkus 2005); hydrocolloid (Zuccarelli 1992; Bowszyc 1995; Thomas 1997; Charles 2002; Vanscheidt 2004); and knitted viscose (Callam 1992).

Primary outcomes

No statistically significant differences were detected between treatment groups for any healing outcome for comparisons of different variants of foam dressings, nor for foam compared with other types of dressings (paraffin gauze, hydrocapillary, hydrocolloid, knitted viscose and protease-modulating matrix). The length of follow up varied across RCTs and ranged between four weeks and one year. Meta-analysis was feasible for one comparison (foam compared with hydrocolloid) where five RCTs were pooled for the outcome of complete healing at 12 to 16 weeks: RR 1.00 (95% CI 0.81 to 1.22).

Secondary outcomes

Secondary outcomes included adverse events, health-related quality of life, costs, pain and dressing performance; outcome definition varied across RCTs. Data were generally sparse for the outcomes of health-related quality of life and costs/resource use.

Where the review authors were able to estimate measures of treatment effect from the available data, no statistically significant between-group differences in the proportion of participants experiencing adverse events were detected when hydrocellular foam dressings were compared with polyurethane foam dressings (Franks 2007), or when foam dressings were compared with hydrocapillary (Norkus 2005), hydrocolloid (Vanscheidt 2004), or knitted viscose dressings (Callam 1992). Regarding dressing performance, data from one RCT suggested that the polyurethane foam dressing may be superior to hydrocellular foam for handling exudate (Andersen 2002), and other data indicated that foam dressings could be better than hydrocolloid for the same outcome plus ease of removal (Bowszyc 1995; Thomas 1997). One RCT described fewer reports of pain for the foam dressing when compared with knitted viscose dressings (Callam 1992), whilst another found no difference in pain scores between groups receiving hydrocellular foam and polyurethane foam dressings (Franks 2007). Otherwise, RCTs either reported no statistically significant differences between groups for these outcomes, or, more commonly, presented only limited information. The secondary outcome data should generally be viewed with caution because of the subjective (and non-blind) nature of the assessments.

 

Overall completeness and applicability of evidence

Participant and intervention characteristics

The majority of participants were ambulatory and had venous leg ulceration confirmed with ABPI assessment; these characteristics are likely to approximate to patients seen in clinical practice. Several RCTs imposed limits to the baseline wound size, sometimes with the idea of recruiting participants with wound sizes which would not exceed the study dressing dimensions (Weiss 1996; Thomas 1997; Andersen 2002; Charles 2002; Vanscheidt 2004). Also, most RCTs listed clinical infection of the ulcer as an exclusion criterion. This may limit applicability to clinical practice, where people with a wide range of wound sizes and/or infected ulcers are likely to be encountered. A further factor which could limit external validity is that nine of the 12 RCTs included were published ten, or more, years ago. If there are differences in earlier versions of foam dressings relative to their more recent counterparts, differential responses to treatment may be observed in clinical practice relative to this body of evidence.

With one exception (Banerjee 1990), all of the included RCTs reported the use of compression therapy as part of the intervention, so we were unable to undertake our planned subgroup analysis for the concurrent presence versus absence of compression. The types of compression therapy differed across the RCTs and included both elastic and short-stretch bandage systems with varying components, and compression stockings.

Primary outcomes

Time to healing was assessed in seven of the 12 included RCTs, however, the analysis method was unclear in one RCT and no data by group were reported (Norkus 2005). Five RCTs evaluated this outcome as a mean time to healing (Bowszyc 1995; Weiss 1996; Andersen 2002; Charles 2002; Vanscheidt 2004). This analysis approach would only account for those participants whose ulcers healed. Participants whose ulcers did not heal during the RCT (censored data) would not have been accounted for by this analysis method which could have resulted in a biased effect estimate (Deeks 2011). Only one RCT, comparing a hydrocellular foam dressing with a polyurethane foam dressing, reported survival analysis as hazard ratios for time to healing, reporting that there was no statistically significant between-group difference over 24 weeks (Franks 2007). The limited way in which this outcome was analysed and reported across the other RCTs restricts any inference regarding the efficacy of foam dressings in terms of time to healing across this body of evidence.

With one exception (Andriessen 2009), all included RCTs reported the proportion of ulcers healed and we were able to estimate between-group differences from these RCTs for this outcome. For three comparisons, estimates were based on a single RCT: foam versus paraffin gauze (Banerjee 1990); foam versus hydrocapillary dressing (Norkus 2005); and foam versus knitted viscose dressing (Callam 1992).

Due to limited reporting in four RCTs that evaluated change in ulcer size (Callam 1992; Weiss 1996; Andersen 2002; Andriessen 2009), specifically in terms of variance estimates, no estimation of between-group differences could be undertaken. None of these RCTs adjusted for baseline ulcer size.

Secondary outcomes

All secondary outcomes varied greatly across the included RCTs in terms of outcome definition, methods of assessment and reporting quality. Lack of available data meant that the review authors were unable to estimate between-group differences in many instances.

In terms of adverse events, only four RCTs provided sufficient data to enable estimation of between-group differences (Callam 1992; Vanscheidt 2004; Norkus 2005; Franks 2007). Cost and resource use data (e.g. mean number of dressing changes) were infrequently reported and where mean values were provided, often lacked variance data, or P values for tests of between-group differences, or both. The method and timing of assessments of pain was varied, and no estimates for between-group differences could be undertaken by the review authors. Outcomes relating to dressing performance were assessed subjectively, using non-validated methods. One RCT reported that dressings were weighed to measure the amount of exudate; whilst this is potentially a more objective method of assessment, no results were presented (Norkus 2005). A quality of life assessment was reported by only one RCT (Norkus 2005), with only limited data provided.

 

Quality of the evidence

Six of the 12 included RCTs were considered to be at overall high risk of bias (Banerjee 1990; Callam 1992; Weiss 1996; Andersen 2002; Charles 2002; Franks 2007), and the remaining six were classified as having unclear risk of bias overall (Zuccarelli 1992; Bowszyc 1995; Thomas 1997; Vanscheidt 2004; Norkus 2005; Andriessen 2009). Of those at high risk of bias, three compared two types of foam dressings (Weiss 1996; Andersen 2002; Franks 2007), one compared a paraffin-impregnated gauze dressing with foam (Banerjee 1990), one compared hydrocolloid dressing with foam (Charles 2002), and one compared knitted viscose dressing with foam dressing (Callam 1992). In three of these, the outcome assessment was not blinded (Weiss 1996; Andersen 2002; Franks 2007), and in four not all participants who were randomised were accounted for in the analysis (Banerjee 1990; Callam 1992; Andersen 2002; Charles 2002). Missing outcome data, due to attrition (drop-out) during the trial or exclusion of participants from the analysis can bias the effect estimate, and lack of blinding of participants or healthcare providers could bias the results by affecting the actual outcomes of the participants in the trial (Higgins 2011a). Two RCTs were described as pilot studies, and had very small sample sizes (Weiss 1996; Andriessen 2009). One RCT presented a unit of analysis issue as, whilst the participants were the unit of randomisation, the unit of analysis was legs, with some participants reported as having bilateral leg ulcers (Bowszyc 1995). An important principle of any RCT is that the analysis must take into account the level at which randomisation occurred and the number of observations in the analysis should match the number of ‘units’ that were randomised (Deeks 2011).

All of the RCTs identified for inclusion in this review were published prior to the current CONSORT (Consolidated Standards of Reporting Trials) guidelines for the reporting of RCTs (Schulz 2010). Key aspects of best practice in RCT design to minimise bias include a robust randomisation method, concealment of treatment group allocation, and, where possible, blinding of participants and trial personnel, and blinded outcome assessment; all of which should be clearly stated in the RCT report. The majority of the included RCTs in this review did not report the method of the random sequence generation or an adequate method of allocation concealment.

The Summary of Findings tables indicate that the current evidence base for the effects of foam dressings compared with alternatives on the healing of venous leg ulcers is mainly of low quality. The quality of available evidence for the outcome of complete healing at 12 to 16 weeks for the comparison of foam and hydrocolloid dressings was moderate. A Summary of Findings table was not generated for the comparison between foam and protease-modulating matrix dressings because only limited data were reported (Andriessen 2009). This highlights a potential gap in the evidence base as there is currently much interest in the role of proteases in chronic wound management (Ovington 2007; Snyder 2012).

 

Potential biases in the review process

In addition to the electronic searches of bibliographic databases, the search for evidence for this review included handsearching, contact with trialists and manufacturers, and the searching of ongoing trials registers. Although this search strategy was comprehensive, the possibility of publication bias cannot be discounted. Nonetheless, given the high or unclear risk of bias of the RCTs identified for inclusion, coupled with the absence of any significant treatment effects on ulcer healing, it is considered unlikely that any additional unpublished data would contribute significantly to the overall findings of this review.

 

Agreements and disagreements with other studies or reviews

The evidence base to guide dressing choice suggests that there is no evidence to support foam dressings as being better or worse than other dressing treatments for the healing of venous leg ulcers. This observation is in agreement with the systematic review by Palfreyman 2007, who concluded that there were insufficient data available to draw strong conclusions about any one dressing type being more effective in healing venous leg ulcers; the review did not comment on foam dressings specifically. Only eight of the 12 RCTs of foam dressings included in this review were included in the review by Palfreyman 2007.

 

Authors' conclusions

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

 

Implications for practice

At present there is no evidence to suggest that foam dressings are better or worse than any other primary wound contact dressing for the healing of venous leg ulcers when applied beneath compression devices. However, the current evidence base is mainly of low quality. The lack of good quality evidence limits specific recommendations regarding the use of any of the dressing types reviewed here for the healing of venous leg ulcers. Further, good quality evidence is required from well designed RCTs prior to it being possible to draw definitive conclusions regarding the efficacy of foam dressings in the management of venous leg ulcers.

 
Implications for research

Most of the RCTs included in this review have methodological and reporting problems.  The majority were published more than 10 years ago, and might not reflect current clinical practice. Those planning future RCTs should consider whether participants are likely to represent patients seen in clinical practice in terms of ulcer size, ulcer duration and the presence of ulcer infection. Ulcer infection was an exclusion criterion in a large number of the included RCTs whereas practitioners are likely to encounter many patients with ulcer infection in clinical practice. Future RCTs should undertake the following in order to minimise bias: robust randomisation and concealment of allocation methods; blinded outcome assessment; analysis by intention-to-treat; and appropriate estimation of time to healing using survival analysis. In addition, future RCTs should be adequately powered to detect treatment effects. Methodological details should be clearly reported in line with the CONSORT (Consolidated Standards of Reporting Trials) guidelines for the reporting of RCTs (Schulz 2010).

Further research that fully investigates the safety and tolerability of wound dressings for venous leg ulcers is required, comprising clear evaluation and reporting of dressing-related adverse events. Quality of life assessment should be undertaken using a valid and reliable assessment instrument and results reported in full. As dressing choice for the management of venous leg ulcers may be guided by cost, future RCTs should present clear and meaningful cost-effectiveness information.

 

Acknowledgements

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

We are very grateful to the following peer referees who provided valuable feedback on the draft of the review: Ruth Foxlee, Richard Kirubakaran, Jane Nadel, Andrea Nelson, Rachel Richardson, and Nikki Stubbs. We also thank Nikki Stubbs for advice regarding the comparability of dressings. Thanks are due to Daisy Gregory, Kirsty Benn-Harris, Belen Corbacho and Jeppe Schroll for their help with translation, and also to Elizabeth Royle for assistance with copy editing. We should like to express appreciation for the support we have received from the staff of the Cochrane Wounds Group - to Ruth Foxlee for advising on the search strategy and running the database searches and to Sally Bell-Syer for helpful advice and assistance with preparing the draft review.

Finally, we would like to thank Smith & Nephew for allowing us to use information contained in the Lothian and Forth Valley Leg Ulcer Healing Trial final report and statistical report (unpublished material) associated with Callam 1992.

 

Data and analyses

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms
Download statistical data

 
Comparison 1. Hydrocellular foam compared with polyurethane foam

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Proportion of ulcers completely healed3Risk Ratio (M-H, Fixed, 95% CI)Subtotals only

    1.1 Ulcers healed at 8 weeks
1118Risk Ratio (M-H, Fixed, 95% CI)1.03 [0.60, 1.78]

    1.2 Ulcers healed at 16 weeks
118Risk Ratio (M-H, Fixed, 95% CI)1.6 [0.75, 3.42]

    1.3 Ulcers healed at 24 weeks
1156Risk Ratio (M-H, Fixed, 95% CI)1.08 [0.85, 1.37]

 2 Participants experiencing adverse events1156Risk Ratio (M-H, Fixed, 95% CI)1.13 [0.69, 1.85]

 
Comparison 2. Paraffin gauze compared with foam

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Proportion of ulcers healed at 17 weeks171Risk Ratio (M-H, Fixed, 95% CI)1.34 [0.61, 2.92]

 
Comparison 3. Hydrocapillary compared with foam

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Proportion of ulcers healed at 12 months197Risk Ratio (M-H, Fixed, 95% CI)0.78 [0.50, 1.21]

 2 Participants experiencing adverse events197Risk Ratio (M-H, Fixed, 95% CI)1.40 [0.62, 3.18]

 
Comparison 4. Hydrocolloid compared with foam

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Proportion of ulcers completely healed at 12 to 16 weeks5Risk Ratio (M-H, Fixed, 95% CI)Subtotals only

    1.1 Meta-analysis including Comfeel study arm from Charles 2002
5387Risk Ratio (M-H, Fixed, 95% CI)0.99 [0.80, 1.22]

    1.2 Meta-analysis including Granuflex study arm from Charles 2002
5389Risk Ratio (M-H, Fixed, 95% CI)1.00 [0.81, 1.24]

    1.3 Meta-analysis including Comfeel and Granuflex study arms combined from Charles 2002
5418Risk Ratio (M-H, Fixed, 95% CI)1.00 [0.81, 1.22]

 2 Participants experiencing dressing-related adverse events1107Risk Ratio (M-H, Fixed, 95% CI)1.22 [0.64, 2.31]

 
Comparison 5. Knitted viscose compared with foam

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Proportion of ulcers healed at 12 weeks1132Risk Ratio (M-H, Fixed, 95% CI)1.35 [0.89, 2.05]

 2 Participants experiencing adverse events1132Risk Ratio (M-H, Fixed, 95% CI)5.0 [0.24, 102.19]

 

Appendices

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms
 

Appendix 1. Glossary

Aetiology: the underlying cause of diseases and disorders (Cochrane Wounds Group Glossary).
Autolytic: the destruction of tissues or cells of an organism by the action of substances, such as enzymes, that are produced within the organism (The Free Medical Dictionary).
Debride/debridement: the removal of foreign material and dead or damaged tissue from a wound (Cochrane Wounds Group Glossary).
Exudate: fluid that leaks out of a wound (Cochrane Wounds Group Glossary).
Fibrinolytic therapy: the use of special drugs to break up blood clots (The Free Medical Dictionary).
Haemodynamic(s): the study of the forces involved in the circulation of blood (The Free Medical Dictionary).
Lipodermatosclerosis: area of pigmentation and hardened skin caused by leakage of red blood cells into the skin. Seen in people with chronic venous insufficiency, affecting the skin just above the ankle (Cochrane Wounds Group Glossary).
Macerate/maceration: the softening and breaking down of skin resulting from prolonged exposure to moisture (The Free Medical Dictionary).
Photoplethysmography: an optically-obtained plethysmograph (an instrument for measuring changes in volume), of a volumetric measurement of an organ (The Free Medical Dictionary).

Proteolysis: the breakdown of proteins into simpler, soluble substances such as peptides and amino acids, as occurs during digestion (The Free Medical Dictionary).
Slough: a layer or mass of dead tissue separated from surrounding living tissue, as in a wound, a sore, or an inflammation (The Free Medical Dictionary).
Vasoactive: causing constriction or dilation of blood vessels (The Free Medical Dictionary).

 

Appendix 2. British National Formulary 2012 categories of dressings

 
Basic wound contact dressings
 
Low-adherence dressings

Low adherence dressings are usually cotton pads that are placed directly in contact with the wound. These dressings can be used as interface layers under secondary absorbent dressings and are suitable for clean, granulating, lightly exuding wounds without necrosis; they protect the wound bed from direct contact with secondary dressings. Care must be taken to avoid granulation tissue growing into the weave of these dressings. Tulle dressings are manufactured from cotton or viscose fibres which are impregnated with white or yellow soft paraffin to prevent the fibres from sticking, but this is only partly successful and it may be necessary to change the dressings frequently. The paraffin reduces absorbency of the dressing. Knitted viscose is an alternative primary dressing to tulle dressings for exuding wounds; it can be used as the initial layer of multi-layer compression bandaging in the treatment of venous leg ulcers (BNF 2013). Examples include Atrauman® (Hartmann) and Tricotex® (Smith and Nephew).

 
Absorbent dressings

Dressings with an absorbent cellulose or polymer wadding layer are suitable for use on moderately to heavily exuding wounds. These may be applied directly to the wound and may be used as secondary absorbent layers in the management of heavily exuding wounds (BNF 2013). Examples include Exu-Dry® (Smith and Nephew) and KerraMax® (Ark Therapeutics).

 
Advanced wound dressings
 
Hydrogel dressings

Hydrogel dressings consist of cross-linked insoluable polymers (i.e. starch or carboxymethylcellulose) and up to 96% water. They are supplied as either flat sheets, or an amorphous hydrogel, or as beads. These dressings are generally used to donate liquid to dry sloughy wounds and facilitate autolytic debridement of necrotic tissue; some also have the ability to absorb very small amounts of exudate. When used, a secondary, non-absorbent dressing is also required (BNF 2013). Examples include ActiFormCool® (Activa) and Intrasite Conformable® (Smith and Nephew).

 
Vapour-permeable films and dressings

Vapour-permeable films and dressings come in the form of a transparent film, usually with an adhesive base that is applied to the wound. Vapour-permeable films and membranes allow the passage of water vapour and oxygen, but are impermeable to water and micro-organisms, and are suitable for lightly exuding wounds. Vapour-permeable films and membranes are unsuitable for infected, large, heavily exuding wounds. Most commonly, they are used as a secondary dressing over alginates or hydrogels (BNF 2013). Examples include OpSite® (Smith and Nephew) and Tegaderm® (3M).

 
Soft polymer dressings

Dressings with soft polymer, often a soft silicone polymer, in a non-adherent or gently-adherent layer are suitable for use on lightly to moderately exuding wounds. For moderately to heavily exuding wounds, an absorbent secondary dressing can be added, or a soft polymer dressing with an absorbent pad can be used (BNF 2013). Examples include Mepilex® (Mölnlycke) and Urgotul® (Urgo).

 
Hydrocolloid dressings

Hydrocolloid dressings are occlusive dressings usually composed of a hydrocolloid matrix bonded onto a vapour-permeable film or foam backing. When in contact with the wound and with exudate, these dressings form a gel to facilitate rehydration in lightly to moderately exuding wounds (BNF 2013). Examples include DuoDERM® Extra Thin (ConvaTec) and Tegaderm® Hydrocolloid (3M).

 
Foam dressings

Foam dressings contain hydrophilic foam and are suitable for all types of exuding wounds. They vary in their ability to absorb exudates; some are suitable only for lightly to moderately exuding wounds, others have a greater fluid-handling capacity. They can be used in combination with other primary wound contact dressings, but are usually placed over the ulcer prior to the application of compression bandages or hosiery, with the intention of promoting healing and preventing the bandages from sticking to the wound. Saturated foam dressings can cause maceration of healthy skin if left in contact with the wound. If used under compression bandaging or compression garments, the fluid handling capacity of foam dressings may be reduced (BNF 2013). Examples include Allevyn® Non-Adhesive (Smith and Nephew) and Biatain® Non-Adhesive (Coloplast).

 
Alginate dressings

Alginate dressings are non-occlusive dressings, made from calcium alginate, or calcium sodium alginate (derived from brown seaweed). The alginate forms a gel when in contact with exudate at the wound surface. This gel can be lifted off during dressing removal or rinsed away with sterile saline. Alginate dressings are highly absorbent and suitable for use on exuding wounds, and for the promotion of autolytic debridement of debris in very moist wounds. Alginate sheets are suitable for use as a wound contact dressing for moderately to heavily exuding wounds and can be layered into deep wounds. If the dressing does not have an adhesive border or integral adhesive plastic film backing, a secondary dressing will be required. Examples include Curasorb® (Covidien) and Sorbsan® (Aspen Medical).

 
Capillary-action dressings

Capillary-action dressings consist of an absorbent core of hydrophilic fibres held between two low-adherent wound-contact layers to ensure no fibres are shed on to the wound surface. Wound exudate is taken up by the dressing and retained within the highly absorbent central layer. Capillary-action dressings are suitable for use on all types of exuding wounds, but particularly on sloughy wounds where removal of fluid from the wound aids debridement (BNF 2013). Examples include Advadraw® (Advancis) and Vacutex® (Protex).

 
Odour-absorbant dressings

Dressings containing activated charcoal are used to absorb odour from wounds. Many odour absorbent dressings are intended for use in combination with other dressings and are often used in conjunction with a secondary dressing to improve absorbency (BNF 2013). Examples include CarboFLEX® (ConvaTec) and CliniSorb® Odour Control Dressings (CliniMed).

 
Antimicrobial dressings
 
Honey

Medical grade honey has antimicrobial and anti-inflammatory properties and can be used for acute or chronic wounds. It is available in sheet-dressing form or as a honey-base topical application applied directly to the wound and covered with a primary low-adherence wound dressing (BNF 2013). Examples include Medihoney® (Medihoney) and Mesitran® (Aspen Medical).

 
Iodine

Both cadexomer–iodine and povidone–iodine release free iodine when exposed to wound exudate. The free iodine acts as an antiseptic on the wound surface, the cadexomer absorbs wound exudate and encourages de-sloughing. Two-component hydrogel dressings containing glucose oxidase and iodide ions generate a low level of free iodine in the presence of moisture and oxygen. A povidone–iodine fabric dressing is a knitted viscose dressing into which povidone–iodine has been incorporated in a hydrophilic polyethylene glycol basis. The iodine has a wide spectrum of antimicrobial activity but it is rapidly deactivated by wound exudate (BNF 2013). Examples include Iodoflex® (Smith and Nephew) and Iodosorb® (Smith and Nephew).

 
Silver

Antimicrobial dressings containing silver are available as: low-adherent dressings, with knitted fabric of activated charcoal, soft polymer dressings, hydrocolloid dressings, foam dressings and alginate dressings. Silver ions exert an antimicrobial effect in the presence of wound exudate. Antimicrobial dressings containing silver should be used only when infection is suspected on the basis of clinical signs or symptoms (BNF 2013). Examples include Acticoat® (Smith and Nephew), Aquacel® Ag (ConvaTec) and Biatain® Ag (Coloplast).

 
Other antimicrobial dressings

A number of dressings that are impregnated with other antimicrobial agents such as chlorhexidine and polyhexanide are also available (BNF 2013). Examples include chlorhexidine gauze dressing, BP 1993 and Suprasorb® X + PHMB (Activa).

 
Specialised dressings
 
Protease-modulating matrix dressings

Protease-modulating matrix dressings alter the activity of proteolytic enzymes in chronic wounds (BNF 2013). Examples include Promogran® (Systagenix) and UrgoStart® (Urgo).

 

Appendix 3. Search strategies for Ovid Medline, Ovid Embase and EBSCO CINAHL

Ovid Medline

1 exp Occlusive Dressings/ (3300)
2 foam*1.tw. (12260)
3 (ActivHeal or Allevyn or Avazorb or Biatain or Copa or LyoFoam or PermaFoam or PolyMem or Suprasorb or Tegaderm or Tielle or Transobent or Trufoam or UrgoCell).tw. (554)
4 or/1-3 (15882)
5 exp Leg Ulcer/ (15502)
6 (varicose ulcer* or venous ulcer* or leg ulcer* or stasis ulcer* or crural ulcer* or ulcus cruris or ulcer cruris).tw. (6261)
7 or/5-6 (16680)
8 4 and 7 (421)
9 randomized controlled trial.pt. (316214)
10 controlled clinical trial.pt. (83227)
11 randomized.ab. (221732)
12 placebo.ab. (127298)
13 clinical trials as topic.sh. (157023)
14 randomly.ab. (160555)
15 trial.ti. (95248)
16 or/9-15 (734544)
17 (animals not (humans and animals)).sh. (3550250)
18 16 not 17 (677587)
19 8 and 18 (87)

Ovid Embase

1 exp occlusive dressing/ (397)
2 exp foam dressing/ (169)
3 foam*1.tw. (13113)
4 (ActivHeal or Allevyn or Avazorb or Biatain or Copa or LyoFoam or PermaFoam or PolyMem or Suprasorb or Tegaderm or Tielle or Transobent or Trufoam or UrgoCell).tw. (699)
5 or/1-4 (14148)
6 exp leg ulcer/ (5933)
7 (varicose ulcer* or venous ulcer* or leg ulcer* or stasis ulcer* or crural ulcer* or ulcus cruris or ulcer cruris).tw. (5351)
8 or/6-7 (7800)
9 5 and 8 (210)
10 Randomized controlled trials/ (21460)
11 Single-Blind Method/ (15103)
12 Double-Blind Method/ (84307)
13 Crossover Procedure/ (30966)
14 (random$ or factorial$ or crossover$ or cross over$ or cross-over$ or placebo$ or assign$ or allocat$ or volunteer$).ti,ab. (911523)
15 (doubl$ adj blind$).ti,ab. (87873)
16 (singl$ adj blind$).ti,ab. (9324)
17 or/10-16 (943260)
18 animal/ (712703)
19 human/ (8384785)
20 18 not 19 (475542)
21 17 not 20 (911699)
22 9 and 21 (44)

EBSCO CINAHL

S8 S4 and S7
S7 S5 or S6
S6 TI ( varicose ulcer* or venous ulcer* or leg ulcer* or stasis ulcer* or crural or cruris ) OR AB ( aricose ulcer* or venous ulcer* or leg ulcer* or stasis ulcer* or crural or cruris )
S5 (MH "Leg Ulcer+")
S4 S1 or S2 or S3
S3 TI ( activheal or allevyn or avazorb or biatain or copa or lyofoam or permafoam or polymem or suprasorb or tegaderm or tielle or transobent or trufoam or urgocell ) OR AB ( activheal or allevyn or avazorb or biatain or copa or lyofoam or permafoam or polymem or suprasorb or tegaderm or tielle or transobent or trufoam or urgocell )
S2 TI foam* OR AB foam*
S1 (MH "Occlusive Dressings")

 

Appendix 4. Dressing manufacturers the review authors contacted regarding ongoing or recently completed trials of alginate dressings

3M
Advancis
Ark Therapeutics
Aspen Medical
Braun
BSN Medical
Coloplast
Covidien
Hartmann
MedLogic
Mölnlycke
Smith & Nephew Healthcare
Systagenix
Urgo

 

Appendix 5. 'Risk of bias' criteria

 
1. Was the allocation sequence randomly generated?

Low risk of bias: the investigators describe a random component in the sequence generation process such as: referring to a random number table; using a computer random number generator; coin tossing; shuffling cards or envelopes; throwing dice; drawing of lots.

High risk of bias: the investigators describe a non-random component in the sequence generation process. Usually, the description would involve some systematic, non-random approach, for example: sequence generated by odd or even date of birth; sequence generated by some rule based on date (or day) of admission; sequence generated by some rule based on hospital or clinic record number.

Unclear risk of bias: insufficient information about the sequence generation process to permit judgement of low or high risk of bias.

 
2. Was the treatment allocation adequately concealed?

Low risk of bias: participants and investigators enrolling participants could not foresee assignment because one of the following, or an equivalent method, was used to conceal allocation: central allocation (including telephone, web-based and pharmacy-controlled randomisation); sequentially-numbered drug containers of identical appearance; sequentially-numbered, opaque, sealed envelopes.

High risk of bias: participants or investigators enrolling participants could possibly foresee assignments and thus introduce selection bias, because using allocation system based on: using an open random allocation schedule (e.g. a list of random numbers); assignment envelopes were used without appropriate safeguards (e.g. when envelopes were unsealed or non-opaque or not sequentially numbered); alternation or rotation; date of birth; case record number; any other explicitly unconcealed procedure.

Unclear risk of bias: insufficient information to permit judgement of low or high risk of bias. This is usually the case if the method of concealment is not described or not described in sufficient detail to allow a definite judgement, for example if the use of assignment envelopes is described, but it remains unclear whether envelopes were sequentially-numbered, opaque and sealed.

 
3. Blinding of participants and personnel - was knowledge of the allocated interventions adequately prevented during the study?

Low risk of bias: no blinding, but the review authors judge that the outcome and the outcome measurement are not likely to be influenced by lack of blinding, or blinding of participants and key study personnel ensured, and unlikely that the blinding could have been broken.

High risk of bias: no blinding or incomplete blinding, and the outcome is likely to be influenced by lack of blinding; or blinding of key study participants and personnel attempted, but likely that the blinding could have been broken, and the outcome is likely to be influenced by lack of blinding.

Unclear risk of bias: insufficient information to permit judgement of low or high risk of bias, or the study did not address this outcome.

 
4. Blinding of outcome assessment - was knowledge of the allocated interventions adequately prevented during the study?

Low risk of bias: no blinding of outcome assessment, but the review authors judge that the outcome measurement is not likely to be influenced by lack of blinding, or blinding of outcome assessment ensured, and unlikely that the blinding could have been broken.

High risk of bias: no blinding of outcome assessment, and the outcome measurement is likely to be influenced by lack of blinding; or blinding of outcome assessment, but likely that the blinding could have been broken, and the outcome measurement is likely to be influenced by lack of blinding.

Unclear risk of bias: insufficient information to permit judgement of low or high risk, or the study did not address this outcome.

 
5. Were incomplete outcome data adequately addressed?

Low risk of bias: no missing outcome data, or reasons for missing outcome data unlikely to be related to true outcome (for survival data, censoring unlikely to be introducing bias), or missing outcome data balanced in numbers across intervention groups, with similar reasons for missing data across groups; or (for dichotomous outcome data), the proportion of missing outcomes compared with observed event risk not enough to have a clinically relevant impact on the intervention effect estimate; or (for continuous outcome data), plausible effect size (difference in means or standardised difference in means) among missing outcomes not enough to have a clinically relevant impact on observed effect size; or missing data have been imputed using appropriate methods.

High risk of bias: reason for missing outcome data likely to be related to true outcome, with either imbalance in numbers or reasons for missing data across intervention groups; or (for dichotomous outcome data), the proportion of missing outcomes compared with observed event risk enough to induce clinically relevant bias in intervention effect estimate; or (for continuous outcome data), plausible effect size (difference in means or standardised difference in means) among missing outcomes enough to induce clinically relevant bias in observed effect size; or ‘as-treated’ analysis done with substantial departure of the intervention received from that assigned at randomisation, or potentially inappropriate application of simple imputation.

Unclear risk of bias: insufficient reporting of attrition/exclusions to permit judgement of low or high risk of bias (e.g. number randomised not stated, no reasons for missing data provided), or the study did not address this outcome.

 
6. Are reports of the study free of suggestion of selective outcome reporting?

Low risk of bias: either the RCT protocol is available and all of the pre-specified outcomes that are in the protocol have been reported in the pre-specified manner or, if the protocol is not available, it is clear that the published report includes all outcomes in the results section that are described as being assessed in the methods section.

High risk of bias: if the RCT protocol is available either, not all of the pre-specified outcomes that are in the protocol are reported, or one or more outcomes are reported using measurements, analysis methods or subsets of the data that are not pre-specified; or one or more reported outcomes were not pre-specified (unless there is justification for their reporting, such as an unexpected adverse event). If the RCT protocol is not available either, not all of the trial’s outcomes have been reported in the results section that are described in the methods section, or one or more of the outcomes is reported using measurements, analysis methods or subsets of the data (e.g. sub-scales) that were not described in the methods section of the report; or one or more of the reported outcomes were not described in the methods section.

Unclear risk of bias: insufficient information to permit judgement of low or high risk of bias.

 

What's new

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

Last assessed as up-to-date: 25 October 2012.


DateEventDescription

26 June 2013AmendedExcluded study Meaume 2012, reason for exclusion clarified



 

Contributions of authors

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

Susan O'Meara: drafted the protocol, responded to the peer referee feedback and agreed the protocol, screened search results and selected relevant studies for inclusion, extracted data, performed risk of bias assessment, analysed data, generated Summary of Findings tables, drafted the review and responded to peer referee and copy editor comments.

Marrissa Martyn-St James: drafted the protocol, responded to the peer referee feedback for the protocol, screened search results and selected relevant studies to be included in the review, extracted data, performed risk of bias assessment and contributed to drafting the review and responding to peer referee comments.

 

Contributions of editorial base

Nicky Cullum: edited the protocol; advised on methodology, interpretation and protocol content. Approved the final protocol prior to submission.
Joan Webster, Editor: Approved the final review prior to submission.
Sally Bell-Syer: co-ordinated the editorial process. Advised on methodology, interpretation and content. Edited the protocol and review.
Ruth Foxlee: designed the search strategy and edited the search methods section.

 

Declarations of interest

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms

This paper presents independent research funded by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research Programme (Grant Reference Number RP-PG-0407-10428). The views expressed are those of the authors (Susan O'Meara and Marrissa Martyn-St James) and not necessarily those of the NHS, the NIHR or the Department of Health.

 

Sources of support

  1. Top of page
  2. Summary of findings    [Explanations]
  3. Background
  4. Objectives
  5. Methods
  6. Results
  7. Discussion
  8. Authors' conclusions
  9. Acknowledgements
  10. Data and analyses
  11. Appendices
  12. What's new
  13. Contributions of authors
  14. Declarations of interest
  15. Sources of support
  16. Index terms
 

Internal sources

  • Department of Health Sciences, University of York, UK.

 

External sources

  • NIHR Programme Grants for Applied Research, UK.
  • NIHR/Department of Health (England), (Cochrane Wounds Groups), UK.

* Indicates the major publication for the study

References

References to studies included in this review

  1. Top of page
  2. AbstractRésumé
  3. Summary of findings
  4. Background
  5. Objectives
  6. Methods
  7. Results
  8. Discussion
  9. Authors' conclusions
  10. Acknowledgements
  11. Data and analyses
  12. Appendices
  13. What's new
  14. Contributions of authors
  15. Declarations of interest
  16. Sources of support
  17. Characteristics of studies
  18. References to studies included in this review
  19. References to studies excluded from this review
  20. References to studies awaiting assessment
  21. References to ongoing studies
  22. Additional references
Andersen 2002 {published data only}
  • Andersen KE, Franken CPM, Gad P, Larsen AM, Larsen JR, van Neer PAFA, et al. A randomized, controlled study to compare the effectiveness of two foam dressings in the management of lower leg ulcers. Ostomy Wound Management 2002;48(8):34-41.
  • Franken K, Neuman HAM, Andersen KE, Larsen AM. The preliminary results of a comparative study on performance characteristics of a new foam dressing Biatain versus Allevyn on venous leg ulcers. 9th European Conference on Advances in Wound Management; 1999, 9-11 November; Harrogate UK. 1999.
  • Larsen AM, Franken K, Vuerstaek J, Wuite J, van Neer PAFA, Andersen KE, et al. A randomised comparative study on performance and safety of Biatain non-adhesive dressing versus Allevyn hydrocellular dressing on venous leg ulcers. 11th Conference of the European Wound Management Association; 2001 17-19 May; Dublin, Ireland. 2001.
Andriessen 2009 {published data only}
  • Andriessen A, Polignano R, Abel M. Monitoring the microcirculation to evaluate dressing performance in patients with venous leg ulcers. Journal of Wound Care 2009;18(4):148-50.
  • Polignano R, Abel M, Andriessen A. The effect of moist wound healing dressing on microcirculation in leg ulcers. A pilot study. 2nd World Union of Wound Healing Societies Meeting; 2004 ,8-13 July; Paris. 2004.
Banerjee 1990 {published data only}
  • Banerjee AK, Levy DW, Rawlinson D. A comparative study of Synthaderm and conventional dressings. Care of the Elderly 1990;2(3):123-5.
Bowszyc 1995 {published data only}
  • Bowszyc J, Silny W, Bowszyc-Dmochowska M, Kazmierowski M, Ben Amer HM, Garbowska T, et al. A randomised controlled comparative clinical trial of Lyofoam versus Granuflex in the treatment of venous leg ulcers. 3rd European Conference on Advances in Wound Management; 1993, 19-22 October; Harrogate, UK. 1994.
  • Bowszyc J, Silny W,   Bowszyc-Dmochowska M, Kaźmierowski M, Ben-Amer HM, Garbowska T, et al. Comparison of two dressings in the treatment of venous leg ulcers. Journal of Wound Care 1995;4(3):106-10.
Callam 1992 {published and unpublished data}
  • Callam MJ, Harper DR, Dale JJ, Brown D, Gibson B, Prescott RJ, et al. Lothian and Forth Valley leg ulcer healing trial Part 1: Elastic versus non-elastic bandaging in the treatment of chronic leg ulceration. Phlebology 1992;7(4):136-41.
  • Callam MJ, Harper DR, Dale JJ, Brown D, Gibson B, Prescott RJ, et al. Lothian and Forth Valley leg ulcer healing trial Part 2: Knitted viscose dressing versus a hydrocellular dressing in the treatment of chronic leg ulceration. Phlebology 1992;7(4):142-5.
  • Smith, Nephew. The Lothian and Forth Valley Leg Ulcer Study. CTR87/29. Final report of a study to compare elastic versus non-elastic bandaging and knitted viscose dressings (Tricotex) versus hydrophilic polyurethane dressings (Allevyn) in the treatment of chronic venous leg ulcers. Volume 1. 1 July 1991.
  • Smith, Nephew. The Lothian and Forth Valley Leg Ulcer Study. Report CTR87/29. Volume 2. Statistical report. 1 July 1991.
Charles 2002 {published data only}
  • Charles H, Callicot C, Mathurin D, Ballard K, Hart J. Randomised, comparative study of three primary dressings for the treatment of venous ulcers. British Journal of Community Nursing 2002;7(6 Suppl):48-54.
  • Charles H, Callicott C, Mathurin D, Ballard K, Hart J. A randomised, comparative study of a recently introduced hydroactive foam dressing versus two well established hydrocolloid dressings in the treatment of venous leg ulcers using short-stretch compression bandages. Fourth Australian Wound Management Association Conference; 2002, 7-10 March; Adelaide, South Australia. 2002.
  • Charles H, Hart J. Pain and pain relief in the treatment of venous leg ulceration. Fourth Australian Wound Management Association Conference; 2002, 7-10 March; Adelaide, South Australia. 2002.
  • Hart J, Charles H, Callicot C, Mathurin D, Ballard C,   Harding KG. A randomised comparative study of a new hydroactive foam dressing versus two hydrocolloid dressings in the treatment of venous ulcers. 8th Annual Meeting of the European Tissue Repair Society ; 1998, August 27-30; Copenhagen, Denmark. 1998.
  • Hart J, Charles H, Callicot C, Mathurin D, Ballard K, Bale S, et al. Randomised, comparative study of Cutinova foam versus Comfeel and Granuflex (improved formulation) in the treatment of venous leg ulcers - interim results. 7th Annual Meeting European Tissue Repair Society; 1997, 23-26 August; Koln, Germany. 1997.
  • Hart J, Charles H, Callicot C, Mathurin D, Ballard K, Harding K. A randomized comparative study of a new hydroactive foam dressing versus two hydrocolloid dressings in the treatment of venous ulcers. Proceedings of the 8th European Conference on Advances in Wound Management; 1998, 26-28 April; Madrid, Spain. 1999.
Franks 2007 {published data only}
  • Franks P, Moody M, Moffatt C. Randomised trial of four layer and cohesive short stretch compression in venous ulceration. Journal of Tissue Viability 2003;13(4):170.
  • Franks PJ, Moody M, Moffatt CJ. Randomised trial of a soft silicone dressing a foam dressing in patients with chronic venous ulceration. 13th Conference of the European Wound Management Association; 2003, 22-24 May; Pisa, Italy. 2003.
  • Franks PJ, Moody M, Moffatt CJ, Hiskett G, Gatto P, Davies C, et al. Randomized trial of two foam dressings in the management of chronic venous ulceration. Wound Repair and Regeneration 2007;15(2):197-202.
  • Franks PJ, Moody M,   Moffatt CJ, Martin R, Blewett R, Seymour E, et al. Randomized trial of cohesive short-stretch versus four-layer bandaging in the management of venous ulceration. Wound Repair and Regeneration 2004;12(2):157-62.
  • Moffatt CJ, Moody M, Franks PJ. Randomised trial comparing four layer with cohesive short stretch compression bandaging in the management of chronic venous ulceration. 13th Conference of the European Wound Management Association; 2003, 22-24 May; Pisa, Italy. 2003.
  • Moody M, Moffatt CJ, Franks PJ. Relative performance of a soft silicone dressing and a foam dressing in patients with chronic venous ulceration. 13th Conference of the European Wound Management Association; 2003, 22-24 May; Pisa, Italy. 2003.
Norkus 2005 {published data only}
  • Jørgensen B, Thomsen JK. Safety and efficacy of a new hydrocapillary dressing in the treatment of leg ulcers. 13th Conference of the European Wound Management Association; 2003, 22-24 May; Pisa, Italy. 2003.
  • Norkus A, Dargis V, Thomsen JK, Harding KG, Ivins N, Serra N, et al. Use of a hydrocapillary dressing in the management of highly exuding ulcers: a comparative study. Journal of Wound Care 2005;14(9):429-32.
Thomas 1997 {published data only}
  • Thomas S, Banks V, Fear-Price M, Hagelstein S, Harding KG, Orpin J, et al. A comparison of two dressings in the management of chronic wounds. Journal of Wound Care 1997;6(8):383-6.
Vanscheidt 2004 {published data only}
  • Jones V. Comparison of the new multilayer composite wound dressing Versiva with Allevyn hydrocellular for managing venous leg ulcers: results of an international multicentre randomised trial. 13th Conference of the European Wound Management Association; 2003, 22-24 May; Pisa, Italy. 2004.
  • Vanscheidt W, Sibbald RG, Eager CA. Comparing a foam composite to a hydrocellular foam dressing in the management of venous leg ulcers: a controlled clinical study. Ostomy Wound Management 2004;50(11):42-55.
Weiss 1996 {published data only}
  • Weiss RA, Weiss MA, Ford RW. Randomized comparative study of Cutinova foam and Allevyn with Jobst UlcerCare stockings for the treatment of venous stasis ulcers. Phlebology 1996;11(Suppl 1):S14-6.
Zuccarelli 1992 {published data only}
  • Zuccarelli F. A comparative study of the hydrocellular dressing Allevyn and the hydrocolloid dressing Duoderm in the local treatment of leg ulcers [Étude comparative du pansement hydrocellulaire Allevyn et du pansement hydrocolloide Duoderm dans le traitement local des ulcères de jambe]. Phlébologie 1992;45(4):529-33.
  • Zuccarelli F. A study to evaluate and compare the performance of a hydrocellular dressing with a hydrocolloid dressing in the treatment of venous leg ulcers. 2nd European Conference on Advances in Wound Management; 1992, 20-23 October; Harrogate, UK. 1993.

References to studies excluded from this review

  1. Top of page
  2. AbstractRésumé
  3. Summary of findings
  4. Background
  5. Objectives
  6. Methods
  7. Results
  8. Discussion
  9. Authors' conclusions
  10. Acknowledgements
  11. Data and analyses
  12. Appendices
  13. What's new
  14. Contributions of authors
  15. Declarations of interest
  16. Sources of support
  17. Characteristics of studies
  18. References to studies included in this review
  19. References to studies excluded from this review
  20. References to studies awaiting assessment
  21. References to ongoing studies
  22. Additional references
Anonoymous 1997 {published data only}
  • Anonymous. Differential therapy of chronic wounds [Ein neuer weg zur therapie von dermatomykosen]. Hautarzt 1997;48(2 Suppl):1-4.
Bale 1998 {published data only}
  • Bale S. A cost-effectiveness study comparing Allevyn* and a hydrocolloid dressing in 100 patients seen in the community. Personal communication, abstract only 1998.
  • Bale S, Hagelstein S, Banks V, Harding KG. Costs of dressings in the community. Journal of Wound Care 1998;7(7):327-30.
  • Harding K, Bale S, Banks V, Orpin J. A cost effectiveness study using Allevyn hydrocellular dressings. Proceedings of the 4th European Conference on Advances in Wound Management; 1994, September 6-9; Copenhagen, Denmark. 1995.
Banks 1997 {published data only}
  • Banks V, Bale S, Harding K, Harding EF. A randomized, stratified, controlled, parallel-group clinical trial of a new polyurethane foam dressing (Lyofoam Extra) versus a hydrocellular dressing in the treatment of moderate to heavily exuding wounds. Proceedings of the 6th European Conference on Advances in Wound Management; 1995, 21-24 November; Harrogate, UK. 1997.
  • Banks V, Bale S, Harding K, Harding EF. An interim analysis of a randomized stratified controlled parallel-group clinical trial of a new polyurethane foam dressing versus a hydrocellular dressing in the treatment of moderate to heavily exuding wounds. Proceedings of the 5th European Conference on Advances in Wound Management; 1995, 21-24 November; Harrogate, UK. 1996.
  • Banks V, Bale S, Harding K, Harding EF. Evaluation of a new polyurethane foam dressing. Journal of Wound Care 1997;6(6):266-9.
  • Banks V, Fear M, Orpin J, Hagelstein S, Thomas N, Colgate G, et al. A comparative open multi-center trial of hydropolymer dressing and hydrocolloid. 9th Annual Symposium on Advanced Wound Care and 6th Annual Medical Research Forum on Wound Repair; 1996, April 20-24; Atlanta. 1996.
  • Banks V, Hagelstein S, Bale S, Harding KG. A comparison of a new polyurethane dressing versus a hydrocellular dressing in the treatment of moderate to heavily exuding wounds. 1996 Symposium on Advanced Wound Care and Medical Research Forum on Wound Repair. 1996.
Berard 1986 {published data only}
  • Bérard P, Montandon S, Jedynak D, Saubier EC. Trial of a hydrocolloid in occlusive dressings in the treatment of skin wounds, "Duoderm" [Ensayo de un hidrocoloide en apósito oclusivo en el tratamiento de escaras cutáneas «Duoderm»]. Revista de Enfermeria 1986;9(1):17-20.
Bressieux 2007 {published data only}
  • Bressieux J, Gerard J, Schmutz J, Bohbot N, Bohbot S. Leg ulcers and a new foam dressing: results of two French multicenter clinical studies. 39th Annual Wound, Ostomy and Continence Nurses Annual Conference. Journal of Wound, Ostomy & Continence Nursing. 2007; Vol. 34:S67. Abstract 1427.
Brown-Etris 2004 {published data only}
  • Brown-Etris M, Limova M. Clinical evaluation of a new foam dressing in the management of venous insufficiency ulcers. 2nd World Union of Wound Healing Societies Meeting; 2004 ,8-13 July; Paris. 2004.
Capillas Pérez 2000 {published data only}
  • Capillas Pérez R, Cabré Aguilar V, Gil Colomé AM, Gaitano García A, Torra i Bou JE. Comparison of the effectiveness and cost of treatment with humid environment as compared to traditional cure. Clinical trial on primary care patients with venous leg ulcers and pressure ulcers [Comparación de la efectividad y coste de la cura en ambiente húmedo frente a la cura tradicional]. Revista de Enfermería 2000;23(1):17-24.
Cherry 1984 {published data only}
Colgan 1996 {published data only}
  • Colgan MP, Teevan M, McBride C, O'Sullivan L, Moore D, Shanik G. Cost comparisons in the management of venous ulceration. Proceedings of the 5th European Conference on Advances in Wound Management; 1995, 21-24 November; Harrogate, UK. 1996.
Collier 1992 {published data only}
  • Collier J. A moist, odour-free environment. A multicentred trial of a foamed gel and a hydrocolloid dressing. Professional Nurse 1992;7(12):804, 806, 808.
Dmochowska 1999 {published data only}
  • Dmochowska M, Prokop J, Bielecka S, Urasinska K, Krolicki A, Nagaj E, et al. A randomized, controlled, parallel group clinical trial of a polyurethane foam dressing versus a calcium alginate dressing in the treatment of moderately to heavily exuding venous leg ulcers. Wounds: A Compendium of Clinical Research and Practice 1999;11(1):21-8.
  • Jasiel E, Nowak A, Gwiezdzinski Z, Bowszyc J, Szarmach H, Blaszsyc. A randomized, controlled, parallel-group clinical trial of a new polyurethane foam dressing (Lyofoam Extra) versus a calcium alginate dressing (Sorbsan) plus a low-adherence dressing (Melolin) in the treatment of moderate to heavily exuding venous leg ulcers. Proceedings of the 6th European Conference on Advances in Wound Management; 1-4 October, 1996; Amsterdam. 1996.
  • Nowak A, Bowszyc P, Blaszczyk M. A randomised, controlled, parallel group clinical trial of a new polyurethane foam dressings versus calcium alginate dressing in the treatment of moderately to heavily exuding venous ulcers. Proceedings of the 5th European Conference on Advances in Wound Management; 1995, 21-24 November; Harrogate, UK. 1996.
Kurring 1994 {published data only}
  • Kurring PA, Roberts CD, Quinlan D. Evaluation of a hydrocellular dressing in the management of exuding wounds in the community. British Journal of Nursing 1994;3(20):1049-53.
Larsen 2005 {published data only}
  • Larsen AM, Vogensen H, Haase L, Jensen N, Florboe NN. Evaluation of a foam dressing with a new soft adherent layer. European Wound Management Association Conference; 2005, 15-17 September; Stuttgart, Germany. 2005.
Meaume 2012 {published data only}
  • Meaume S, Dompmartin A, Schmutz J-L, Ourabah Z, Thirion V, Thirion V, et al. Management of venous leg ulcers with two active wound dressings. Results of a randomized clinical trial. 18th Conference of the European Wound Management Association, 14-16 May 2008, Lisbon, Portugal. 2008.
  • Meaume S, Schmutz J-L, Dompmartin A, Fays S, Ourabah Z, Thirion V, et al. Management of venous leg ulcers with two active wound dressings. Results of a randomized clinical trial. 3rd Congress of the World Union of Wound Healing Societies Meeting; 2008, 4-8 June; Toronto, Canada,  2008. Abstract number OR047. 2008.
  • Meaume S, Truchetet F, Cambazard F, Lok C, Debure C, Dalac S, et al. A randomized, controlled, double-blind prospective trial with a Lipido-Colloid Technology-Nano-OligoSaccharide Factor wound dressing in the local management of venous leg ulcers. Wound Repair and Regeneration 2012;20(4):500-11.
  • Schmutz J-L, Meaume S, Fays S, Ourabah Z, Guillot B, Thirion V, et al. Evaluation of the nano-oligosaccharide factor lipido-colloid matrix in the local management of venous leg ulcers: results of a randomised, controlled trial. International Wound Journal 2008;5(2):172-82.
Moffatt 1992 {published data only}
  • Moffatt CJ, Oldroyd MI, Dickson D. A trial of hydrocolloid dressing in the management of indolent ulceration. Journal of Wound Care 1992;1(3):20-2.
Moody 1991 {published data only}
  • Moody M. Tissue viability. Calcium alginate: a dressing trial. Nursing Standard 1991;13(Special supplement):3-6.
Mulder 1995 {published data only}
  • Mulder G, Jensen J, Seeley J. Use of a hyrocellular [sic] dressing versus a calcium alginate in the treatment of venous leg ulcers. 5th Annual Meeting of the European Tissue Repair Society; 1995, August 30-September 2; Padova, Italy. 1995.
Pessenhofer 1992 {published data only}
  • Pessenhofer H, Stangl M. The effect of a two-layered polyurethane foam wound dressing on the healing of venous leg ulcers. Journal of Tissue Viability 1992;2(57):57-61.
  • Pessenhofer H, Stangl M. The effect on wound healing of venous leg ulcers of a two-layered polyurethane foam wound dressing [Beinflussung des heilungsverlaufs von venösen ulcera cruris durch eine zweischichtige polyurethan-schaumstoff-wundauflage]. Arzneimittel-Forschung 1989;39(9):1173-7.
Pottle 1987 {published data only}
  • Pottle B. Leg ulcers. Trial of a dressing for non-healing ulcers. Nursing Times 1987;83(12):54-8.
Price 2004 {published data only}
  • Price P. Health-related quality of life aspects after treatment with a foam dressing and a silver containing foam dressing in chronic leg ulcers. 2nd World Union of Wound Healing Societies Meeting; 2004, 8-13 July; Paris. 2004.
Reynolds 2004 {published data only}
  • Reynolds T, Russell L, Deeth M, Jones H, Birchall L. A randomised controlled trial comparing Drawtex with standard dressings for exuding wounds. Journal of Wound Care 2004;13(2):71-4.
Romanelli 1999 {published data only}
  • Romanelli M, Schipani E, Piaggesi A, Barachini P. Evaluation of maceration under moist wound healing dressings. Proceedings of the 8th European Conference on Advances in Wound Management; 1998, 26-28 April; Madrid, Spain. 1998.
Rubin 1990 {published data only}
  • Rubin JR, Alexander J, Plecha EJ, Marman C. Unna's boot vs polyurethane foam dressings for the treatment of venous ulceration. A randomized prospective study. Archives of Surgery 1990;125(4):489-90.
Schulze 2001 {published data only}
  • Schulze H-J, Lane C, Charles H, Ballard K, Hampton S, Moll I. Evaluating a superabsorbent hydropolymer dressing for exuding venous leg ulcers. Journal of Wound Care 2001;10(1):511-8.
Scurr 1993 {published data only}
  • Scurr JH, Wilson LA, Coleridge Smith PD. A comparison of the effects of semipermeable foam and film secondary dressings over alginate dressings on the healing and management of venous ulcers. Wounds: A Compendium of Clinical Research and Practice 1993;5(6):259-65.
Sironi 2003 {published data only}
  • Sironi G, Losa S, Di Luca G, Pezzoni F. Patients with venous leg ulcers in vascular surgery treatment with Intrasite gel, Opsite Flexigrid, Allevyn and Flexobande Legere/Forte:  a randomised comparative clinical evaluation - an interim report. 13th Conference of the European Wound Management Association; 2003, 22-24 May; Pisa, Italy. 2003.
  • Sironi G, Losa S, Di Luca G, Pezzoni F. Treatment of venous leg ulcers with Intrasite gel OpSite Flexigrid, Allevyn hydrocellular dressing and Flexobande (elastic compression bandage) in vascular surgery.  A protocol for clinical evaluations. 3rd European Conference on Advances in Wound Management; 1993, 19-22 October; Harrogate, UK. 1994.
van Rijswijk 1985 {published data only}
  • van Rijswijk L, Brown D, Friedman S, Degreef H, Roed Petersen J, Borglund E, et al. Comparing a foam composite to a hydrocellular foam dressing in the management of venous leg ulcers: a controlled clinical study. Ostomy Wound Management 2004;50(11):42-55.
Verdu Soriano 2006 {published data only}
  • Verdú Soriano J, Nolasco Bonmati A, López Casanova P, Torra i Bou J-E. "Auriga-04" study on the use of a range of Allevyn hydro-cellular dressings in the treatment of bed sores and leg ulcers by primary health care professionals [Estudio «Auriga-04» aplicación y utilidad de los resultados de la investigación con la gama de apósitos Allevyn en atención primaria]. Revista de Enfermeria 2006;29(4):43-9.
Winter 1996 {published data only}
  • Winter A, Hewitt H. Testing a hydrocolloid. Nursing Times 1990;86(50):59-62.
Wollina 1997 {published data only}
  • Wollina U. Topical therapy of chronic wounds with a new hydropolymer dressing - clinical experience in 478 patients [Lokaltherapie chronischer wunden mit einem neuen hydropolymerverband - klinische erfahrungen bei 478 patienten]. Zeitschrift für Hautkrankheiten 1997;72(7):500-6.

References to studies awaiting assessment

  1. Top of page
  2. AbstractRésumé
  3. Summary of findings
  4. Background
  5. Objectives
  6. Methods
  7. Results
  8. Discussion
  9. Authors' conclusions
  10. Acknowledgements
  11. Data and analyses
  12. Appendices
  13. What's new
  14. Contributions of authors
  15. Declarations of interest
  16. Sources of support
  17. Characteristics of studies
  18. References to studies included in this review
  19. References to studies excluded from this review
  20. References to studies awaiting assessment
  21. References to ongoing studies
  22. Additional references
Jørgensen 2008 {published data only}
  • Jørgensen B, Sulcaite R, Vilkevicius G, Bech-Thomsen N, Rimdeika R, Gottrup F. A randomised, controlled trial on safety and performance of a new foam dressing on venous leg ulcers. EWMA Journal 2008;8(2 (Supp)):138, Abstract no. P69.
Romanelli 2008 {published data only}
  • Andriessen A, Dini V, Barbanera S, Bertone MS, Brilli C, Abel M, et al. Improvent of peri-wound skin condition increases venous leg ulcer healing rates: rct [sic] comparing a bio-cellulose dressing with a foam. EWMA Journal 2011;11(2 Suppl):69.
  • Romanelli M, Dini V, Barbanera S, Bertone MS, Brilli C, De Lorenzo A. Improvement of treatment in patients with venous leg ulcers by a new pain-reducing wound dressing with hydrobalance. EWMA Journal 2008;8(2 (Supp)):286, Abstract no. P366.

References to ongoing studies

  1. Top of page
  2. AbstractRésumé
  3. Summary of findings
  4. Background
  5. Objectives
  6. Methods
  7. Results
  8. Discussion
  9. Authors' conclusions
  10. Acknowledgements
  11. Data and analyses
  12. Appendices
  13. What's new
  14. Contributions of authors
  15. Declarations of interest
  16. Sources of support
  17. Characteristics of studies
  18. References to studies included in this review
  19. References to studies excluded from this review
  20. References to studies awaiting assessment
  21. References to ongoing studies
  22. Additional references
Badiavas 2011 {published data only}
  • Badiavas E. A post marketing study of Apligraf in non-healing wounds of subjects with venous leg ulcers. http://clinicaltrials.gov/ct2/show/study/NCT01327937?term=apligraf&rank=1 (accessed 22 Aug 2012).
Bayer 2009 {published data only}
  • Bayer. Silica gel fiber wound dressing for chronic venous leg ulcers. http://clinicaltrials.gov/ct2/show/study/NCT00998673?term=silica+gel+fiber+wound+dressing&rank=1 (accessed 22 Aug 2012).
Vas 2008 {published data only}
  • Vas J. Effectiveness of acupuncture, special dressings and simple, low-adherence dressings for healing venous leg ulcers in primary healthcare. http://www.controlled-trials.com/mrct/trial/2285898/leg+ulcers (accessed 12 May 2012).

Additional references

  1. Top of page
  2. AbstractRésumé
  3. Summary of findings
  4. Background
  5. Objectives
  6. Methods
  7. Results
  8. Discussion
  9. Authors' conclusions
  10. Acknowledgements
  11. Data and analyses
  12. Appendices
  13. What's new
  14. Contributions of authors
  15. Declarations of interest
  16. Sources of support
  17. Characteristics of studies
  18. References to studies included in this review
  19. References to studies excluded from this review
  20. References to studies awaiting assessment
  21. References to ongoing studies
  22. Additional references
Al-Kurdi 2008
Augustin 2012
  • Augustin M, Brocatti LK, Rustenbach SJ, Schäfer I, Herberger K. Cost-of-illness of leg ulcers in the community. International Wound Journal 2012;Oct 1:doi: 10.1111/j.1742-481X.2012.01089.x.
Becker 2011
  • Becker LA, Oxman AD. Chapter 22: Overviews of reviews. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
BNF 2013
  • British National Formulary, British Medical Association, British Royal Pharmaceutical Society of Great Britain. British National Formulary 65. London: British Medical Association, 2012.
Briggs 2012
Cochrane Wounds Group Glossary
  • Cochrane Wounds Group Glossary. http://wounds.cochrane.org/glossary (accessed 23 April 2010).
Davies 2005
  • Davies CE, Turton G, Woolfrey G, Elley R, Taylor M. Exploring debridement options for chronic venous leg ulcers. British Journal of Nursing 2005;14(7):393-7.
Deeks 2011
  • Deeks JJ, Higgins JPT, Altman DG on behalf of the Cochrane Statistical Methods Group. Chapter 9:  Analysing data and undertaking meta-analyses. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
Doughty 2007
  • Doughty DB, Holbrook R. Lower-extremity ulcers of vascular etiology. In: Bryant RA, Nix DP editor(s). Acute and chronic wounds: current management concepts. 3rd Edition. St Louis, Missouri, USA: Mosby, 2007.
Flemming 2001
Gohel 2005
  • Gohel MS, Taylor M, Earnshaw JJ, Heather BP, Poskitt KR, Whyman MR. Risk factors for delayed healing and recurrence of chronic venous leg ulcers - an analysis of 1324 legs. European Journal of Vascular and Endovascular Surgery 2005;29(1):74-7.
Graham 2003
  • Graham ID, Margaret B, Harrison MB, Nelson EA, Lorimer K, Fisher A. Prevalence of lower-limb ulceration: a systematic review of prevalence studies. Advances in Skin and Wound Care 2003;16(6):305-16.
Herber 2007
Higgins 2003
Higgins 2011a
  • Higgins JPT, Altman DG, Sterne JAC on behalf of the Cochrane Statistical Methods Group and the Cochrane Bias Methods Group. Chapter 8: Assessing risk of bias in included studies. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
Higgins 2011b
  • Higgins JPT, Altman DG, Sterne JAC on behalf of the Cochrane Statistical Methods Group and the Cochrane Bias Methods Group. Chapter 16: Special topics in statistics. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
Iglesias 2004
  • Iglesias C, Nelson EA, Cullum NA, Torgerson DJ on behalf of the VenUS Team. VenUS I: a randomised controlled trial of two types of bandage for treating venous leg ulcers. Health Technology Assessment 2004; Vol. 8, issue 29.
König 2005
  • König M, Vanscheidt W, Augustin M, Kapp H. Enzymatic versus autolytic debridement of chronic leg ulcers: a prospective randomised trial. Journal of Wound Care 2005;14(7):320-3.
Lefebvre 2011
  • Lefebvre C, Manheimer E, Glanville J, on behalf of the Cochrane Information Retrieval Methods Group. Chapter 6: Searching for studies. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
Liberati 2009
  • Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gotzsche PC, Ioannidis JP, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. PLoS Medicine 2009;6:e1000100.
Lorimer 2003
  • Lorimer K, Harrisaon MB, Graham ID, Friedberg E, Davies B. Assessing venous ulcer population characteristics and practices in a home care community. Ostomy Wound Management 2003;49(5):32-43.
Margolis 2002
Margolis 2004
Moffatt 1995
  • Moffatt CJ, Dorman MC. Recurrence of leg ulcers within a community ulcer service. Journal of Wound Care 1995;4(2):57-61.
Moffatt 2004
Moffatt 2007
  • Moffatt C. Compression therapy in practice. Aberdeen: Wounds UK Publishing, 2007.
Morris 2003
  • Morris L. Descriptive evaluation of Alione hydrocapillary dressing. British Journal of Nursing 2003;12(10):630-5.
Nelzen 2008
  • Nelzen O. Prevalence of venous leg ulcer: the importance of the data collection method. Phlebolymphology 2008;15(4):143-50.
O'Meara 2007
  • O'Meara SM. Studies in chronic wound healing: synthesising data and measuring ulcer dimensions. PhD thesis. University of York 2007.
O'Meara 2009
O'Meara 2010
Ovington 2007
Palfreyman 2006
Palfreyman 2007
Parmar 1998
Persoon 2004
Ragnarson Tennvall 2005
Ravaghi 2006
RCN 2006
  • Royal College of Nursing. Clinical practice guidelines. The nursing management of patients with venous leg ulcers. Available from http://www.rcn.org.uk/__data/assets/pdf_file/0003/107940/003020.pdf (accessed 7 March 2012) 2006.
RevMan 2012
  • The Nordic Cochrane Centre, The Cochrane Collaboration. Review Manager (RevMan). 5.2. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2012.
Robson 2006
Ruckley 1998
  • Ruckley CV. Caring for patients with chronic leg ulcer. BMJ 1998;316(7129):407-8.
Schulz 2010
  • Schulz KF, Altman DG, Moher D, for the CONSORT Group 2010. CONSORT 2010 Statement: updated guidelines for reporting parallel group randomised trials. Annals of Internal Medicine 2010;152(11):1-8.
Schünemann 2009
  • Schünemann H, Brożek J, Oxman A, editors. GRADE handbook for grading quality of evidence and strength of recommendation. Version 3.2 [updated March 2009]. The GRADE Working Group, 2009. Available from http://www.cc-ims.net/gradepro.
Schünemann 2011a
  • Schünemann HJ, Oxman AD, Higgins JPT, Vist GE, Glasziou P, Guyatt GH. Chapter 11: Presenting results and ‘Summary of findings' tables. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
Schünemann 2011b
  • Schünemann HJ, Oxman AD, Vist GE, Higgins JPT, Deeks JJ, Glasziou P, et al. Chapter 12: Interpreting results and drawing conclusions. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
SIGN 2011a
  • Scottish Intercollegiate Guidelines Network (SIGN). Management of chronic venous leg ulcers. A national clinical guideline. Available from www.sign.ac.uk 2011.
SIGN 2011b
  • Scottish Intercollegiate Guidelines Network (SIGN). Search filters. http://www.sign.ac.uk/methodology/filters.html#random (accessed 7 March 2012).
Snyder 2012
  • Snyder R, Serena T, Cullen B, Nisbet L. The importance of proteases in wound healing and wound assessment. E-Poster 379. 22nd Conference of the European Wound Management Association. Vienna; 23-25 May, 2012. 2012.
Srinivasaiah 2007
  • Srinivasaiah N, Dugdall H, Barrett S, Drew PJ. A point prevalence survey of wounds in north-east England. Journal of Wound Care 2007;16(10):413-9.
Sterne 2011
  • Sterne JAC, Egger M, Moher D on behalf of the Cochrane Bias Methods Group. Chapter 10:  Addressing reporting biases. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
Sussman 2010
  • Sussman 2010. Technology update: understanding foam dressings. Wounds International. Product Reviews 2010;1(2):1-6.
The Free Medical Dictionary
  • The Free Medical Dictionary. http://medical-dictionary.thefreedictionary.com (accessed 23 April 2012).
Vowden 2009a
  • Vowden KR, Vowden P. The prevalence, management and outcome for patients with lower limb ulceration identified in a wound care survey within one English health care district. Journal of Tissue Viability 2009;18(1):13-9.
Vowden 2009b
  • Vowden KR, Vowden P. A survey of wound care provision within one English health care district. Journal of Tissue Viability 2009;18(1):2-6.
Vowden 2009c
  • Vowden K, Vowden P. The resource costs of wound care in Bradford and Airedale primary care trust in the UK. Journal of Wound Care 2009;18(3):93-102.
Winter 1963