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INTRODUCTION

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES

Assessing physical disability is of critical importance to arthritis research, care, and policy. In measuring physical disability, researchers acknowledge the need to gauge health in terms of the impact of a condition on a person's ability to perform everyday activities and not just using indices like mortality and the manifestation of disease symptoms. As a result, it is not surprising that a wide range of physical disability measures exists. For example, there are disability scales tailored to specific arthritis diagnoses, including rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, scleroderma, psoriatic arthritis, lupus, and gout; there are region-specific measures of physical disability for knees, hips, the neck, back, and upper extremities, measures that span childhood, adolescence, and adulthood, and domain-specific measures that assess difficulties with diverse aspects of particular roles like paid employment. Many general health status and quality of life measures also include subscales assessing physical disability.

Yet, the term physical disability is one that is often used loosely and interchangeably with a variety of other terms. These include activity limitations, functional limitations, and functional disability. More recently, social functioning has been introduced into the research lexicon. In general, all of these terms reflect the concept of physical disability as one where a physical health condition or disease is evaluated in terms of its impact, difficulties, or limitations on a range of tasks, activities, or roles that are considered typical of everyday life. It is this definition of physical disability that we adopt for our review. However, not every measure taps the full breadth of tasks, activities, and roles encompassed by this definition. For example, early measures of physical disability, labeled activity or functional limitation measures, were primarily aimed at basic aspects of daily living such as eating, bathing, dressing, using the toilet, and household mobility, and were often used to assess independence in older or chronically ill adults. These measures soon were enhanced with items tapping physical disability with instrumental activities of daily life such as shopping, household chores, meal preparation, and community mobility. In measuring instrumental activities, researchers recognized more complex tasks and acknowledged a wide range of personal, social, and environmental factors beyond disease that could influence disability. Moreover, whereas measures of activity limitations were often used in samples of individuals with relatively severe health problems or impairments, measures of instrumental activity limitations were applied to broader cross-sections of the population, including those with less impairment. Most recently, measures of physical disability or disablement have been applied even more broadly to capture a complete range of functional states from body structures and functions to impairments, activities, and participation in society or social functioning in areas such as work, leisure activities, socializing, and intimate relationships. This broad use of the concept of disability is exhibited most clearly in the World Health Organization's (WHO) International Classification of Functioning, Disability, and Health (1).

Because there are numerous measures capturing diverse domains of physical disability, not all are reviewed here, although some are reviewed elsewhere in this issue (e.g., articles on functional limitations, social functioning and participation, work disability, health status and quality of life, and the large number of versions of the Health Assessment Questionnaire applied to different disease diagnoses, body regions, and ages). In selecting measures for this article, we supplemented the physical disability measures reviewed elsewhere with those that span a cross-section of tasks, activities, and roles that make up daily life. We begin with an early, arthritis-specific, physical disability measure, the Arthritis Impact Measurement Scales 2 (AIMS2) and AIMS2-Short Form. The remaining measures reviewed are not disease specific. However, they allow arthritis researchers to collect data on physical disability, its determinants, and outcomes that are useful for comparing within and across diseases and health conditions. The Organization for Economic Cooperation and Development (OECD) Long-Term Disability (LTD) Questionnaire is one of the first broadly focused measures developed to assess physical disability. It is reviewed here, particularly because it is an early precursor to newer measures like the EQ-5D developed by the European Quality of Life Group and the WHO Disability Assessment Schedule II (WHODASII). We include these latter measures in our review as examples of easy-to-administer questions that are being applied to a wide range of diseases and health states. Finally, we include the Late-Life Function and Disability Instrument (LLFDI), full and abbreviated versions. These measures reflect examples of efforts researchers have made to expand physical disability beyond tasks and activities to include limitations in roles like socializing with others, employment, care of others, leisure, and hobbies.

No one measure reviewed in this article is likely to satisfy the needs of all researchers wanting to measure physical disability. Some measures will be too narrowly focused either in their emphasis on arthritis or in the domains they capture (e.g., basic activities of daily living and not instrumental activities or social roles). Others may provide a broad overview or snapshot of disability, but lack detail that would be sufficient for clinicians in making decisions for patients. For example, some measures use a time frame of today (e.g., EQ-5D) or the last month (e.g., AIMS2, WHODASII); others ask respondents about “typical” difficulties (e.g., OECD LTD Questionnaire, LLFDI). The former time frame can give a relatively accurate picture of disability, but if one's current disability or disability in the previous month was unusual in some respects, it may not characterize the overall impact of a health condition on a person's life. The latter time frame results in respondents trying to characterize their disability in terms of what is usual or normal for them. This might be very helpful in getting an overall picture of the impact of a health condition, but it may not be optimal for detecting small changes in health or for use in some kinds of intervention or longitudinal research or when a person's appraisal of what is normal for them changes or evolves over time. Despite this, the different measures of physical disability capture the impact of arthritis on a broad range of activities and roles that are meaningful to people living with the disease. They are useful in descriptive or surveillance studies identifying areas of need and they have the potential to generate information on the societal impact or burden of disease. All of the measures would benefit from additional testing to examine their predictive validity and responsiveness to change. However, many are promising as outcomes for intervention research.

The interest and importance of measuring a broad range of activities and roles affected by health conditions like arthritis means that we will likely continue to see refinements, greater sophistication, and greater standardization of measures. For example, one innovation of some measures (e.g., WHODASII, EQ-5D) has been the international, collaborative methods used. Numerous countries participated in the design of questions at the outset of the measure's development. Traditionally, measures have been developed with little or no input from other cultures and then simply translated into other languages. This has sometimes resulted in poorer validity when the measure is applied to diverse samples. Item banks and computerized adaptive testing are also being applied to measures of disability to maximize the information gained from measures while minimizing time and costs of measurement administration. Researchers also are eager to test measures across different diseases for the purposes of comparative studies, to adapt measures to assess the personal and economic cost of disease, and to use physical disability measures for evaluating treatments and interventions. As such, we can anticipate continued improvements in the quality and application of physical disability measures over time.

ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES

Description

Purpose.

The AIMS2 is an arthritis-specific health status measure that assesses physical functioning, pain, psychological status, social interactions and support, health perceptions, and demographic and treatment information. The AIMS2 has superseded the original AIMS and was revised in 1992 to have greater specificity and sensitivity, and to incorporate client perceptions of performance (2). Development work for the AIMS2 was in patients with rheumatoid arthritis (RA) and osteoarthritis (OA). A short form of the AIMS2 has been developed (3). Information about the AIMS2-Short Form is presented elsewhere in this article.

Content.

The physical function component of the AIMS2 (i.e., physical disability) comprises 6 domains: mobility (using transportation, errands, assistance getting around outside the home); walking and bending (vigorous activities, bending, lifting, stooping, climbing stairs); hand and finger function (writing with a pen or pencil, buttoning clothing, opening jars); arm function (putting on a pullover sweater, combing or brushing your hair, reaching); self-care tasks (help with bathing, dressing, using the toilet); and household tasks (meal preparation, housework, laundry). Other domains not described in detail here are symptoms (pain), role (work), social interaction (social activity, family support), and affect (tension, mood).

Number of items.

The total AIMS2 has 78 questions. Factor analysis yields a separate physical function component of 28 items. The 28 items capture 6 domains: mobility (5 items); walking and bending (5 items); hand and finger function (5 items); arm function (5 items); self-care tasks (4 items); and household tasks (4 items).

Response options/scale.

Physical function subscales measure trouble (or absence of trouble) with mobility, walking and bending, hand and finger function, and arm function and are assessed on a 5-point Likert-type scale with 1 = all days, 2 = most days, 3 = some days, 4 = few days, and 5 = no days. Subscales measuring self-care and household tasks are assessed with 1 = always, 2 = very often, 3 = sometimes, 4 = almost never, and 5 = never.

Recall period for items.

The past month.

Endorsements.

There are no known endorsements.

Examples of use.

The AIMS2 has been used as an outcome examining the impact of clinical care in RA (4–7), OA (8), psoriatic arthritis (9–12), ankylosing spondylitis (13, 14), fibromyalgia (15, 16), carpal tunnel syndrome and Colles fracture (17), hemophilia (18–20), and in patients undergoing joint replacement surgery (21).

Practical Application

How to obtain.

Available at the following URLs: www.rheumatology.org/practice/clinical/clinicianresearchers/; www.proqolid.org/instruments/arthritis_impact_measurement_scales_aims2. Copyright is held by Boston University, but there is free access. Also available at reference (22).

Method of administration.

Self-administered.

Scoring.

The AIMS2 User's Guide provides scoring information for the complete scale. Some items are reverse scaled and require recoding prior to scoring. Scores for each of the 6 domains of physical functioning are summed and then converted to a range of 0–10 using a simple mathematical transformation available in the User's Guide. Computer scoring is available. If an item is missing, the average score of the other scale items may be substituted prior to calculation of subscores. Multiple omissions require a case-by-case examination.

Score interpretation.

High scores indicate poor health. No cut off values or normative values are available but scale scores may be adjusted to account for comorbidities. AIMS2 scales were originally discussed as 3 or 5 dimensions of health status. However, many studies discuss the measure using 5 dimensions: physical function, symptom, affect, social interaction, and role.

Respondent burden.

Approximately 20–25 minutes to complete. It is a lengthy questionnaire, but not burdensome in terms of reading level required or emotional content.

Administrative burden.

Scoring by hand completed in approximately 10 minutes; computerized scoring can be completed in seconds. Minimal training required. User's Guide is available online from the Patient-Reported Outcome and Quality of Life Instruments Database (PROQOLID) web page provided above.

Translations/adaptations.

Available in English, French, Dutch, Swedish, Chinese, Norwegian, Italian, German, Japanese, Spanish, Greek, Hebrew, Portuguese, Turkish, Russian, and Persian. However, authors of some translated versions of the AIMS2 note the need for more psychometric work (23–27). The AIMS2 has been adapted to ankylosing spondylitis (13). Also, an AIMS scale for children and older adults (Geri-AIMS) has been created. However, these latter scales were based on the original AIMS (not the AIMS2) (28, 29).

Psychometric Information

Method of development.

The AIMS2 was developed to enhance the original AIMS. Original scale items were developed to go beyond disease activity and to measure a broader array of components identified as important to health by the World Health Organization. The original AIMS contained 45 items. In the AIMS2, 35 items were unchanged, 4 were revised, and 6 were deleted. Patients with RA and OA were involved in testing the measure. Subscales were generated using principal components factor analysis. Test–retest reliabilities used intraclass correlation coefficients, Cronbach's alpha, and kappa statistics.

Acceptability.

The AIMS2 is easy to complete. Missing data are not noted as a problem. However, floor and ceiling effects have been observed depending on the patient group observed (26, 27).

Reliability.

Much of the psychometric work available on reliability has used the original AIMS. In Meenan et al (2), within-scale principal component factor analysis found that items in the physical function subscale loaded on a single factor, except for mobility items, which loaded on more than one factor among those with OA. Internal consistency using Cronbach's alpha coefficients ranges from 0.72–0.91 for patients with RA (n = 299) and 0.74–0.96 for patients with OA (n = 109) across the entire 12 scales. Test–retest intraclass correlation coefficients range from 0.78–0.94 over a 2-week period (2). Other studies have found comparable results for internal consistency and test–retest reliability (24, 26, 30). Examining the 6 components of physical function, Meenan et al (2) report Cronbach's alphas for RA (n = 299) and OA (n = 109), respectively, as mobility level = 0.85 and 0.83, walking and bending = 0.84 and 0.88, hand and finger function = 0.90 and 0.87, arm function = 0.82 and 0.74, self-care tasks = 0.81 and 0.95, and household tasks = 0.88 and 0.81. Intraclass correlation coefficients were calculated on a subset of 45 respondents with RA or OA with a test–retest time frame of 2–3 weeks: mobility = 0.91, walking and bending = 0.92, hand and finger function = 0.94, arm function = 0.92, self-care tasks = 0.81, and household tasks = 0.81.

Validity.

The content of the AIMS2 focuses mainly on function and basic tasks of daily living, with less attention given to disability with instrumental activities or social roles. Much of the psychometric work available related to criterion or construct validity has used the original AIMS. The AIMS scales measuring physical functioning were correlated as expected with other measures of function (e.g., Health Assessment Questionnaire [HAQ]) (i.e., criterion validity) and with disease activity (e.g., swollen joint count, pain, erythrocyte sedimentation rate) (i.e., construct validity) (12, 31–34). AIMS2 scale scores were significantly associated with areas patients identified as problematic (2); moderate to high correlations ranging from 0.75–0.89 were also found with other measures of disability (e.g., HAQ, Short Form 36 [SF-36]) (2, 12, 35, 36) and low to moderate correlations (0.3–0.5) with measures of disease activity among patients with ankylosing spondylitis and psoriatic arthritis (10, 36). The factor structure identified by the scale developers has not been examined as part of validity testing.

Ability to detect change.

The AIMS2 was designed to be sensitive to improvements produced by arthritis therapy (2). Physical function scores were found to provide somewhat greater sensitivity to change than the modified HAQ in one study (37) and similar responsiveness in 2 others (4, 38). Comparability also exists between the AIMS2 and SF-36 with some studies finding slightly more responsiveness in the SF-36 (38) and others reporting better responsiveness for the AIMS2 (6).

Critical Appraisal of Overall Value to the Rheumatology Community

Strengths.

The AIMS2 has been widely used across different types of arthritis diagnoses and exhibits good psychometric properties. It has been used in intervention research as a patient-oriented outcome and demonstrates comparable responsiveness and sensitivity to change as other disability and global health status measures, including the HAQ and SF-36. Use of the physical function component of the AIMS2 along with the other components allows the evaluation of pain and patient perceptions of the broad impact of arthritis on their lives.

Caveats and cautions.

The length and time needed to complete the AIMS2 may hinder its use in clinical, community, and population health research. As a disease-specific measure, the AIMS2 is limited in its potential for use in comparative disease studies. In recent years, the AIMS2 has largely been supplanted by other measures of disability, including the AIMS2-Short Form, HAQ, and SF-36. The AIMS2 is somewhat limited in the scope of its questions assessing disability compared to other measures.

Clinical usability.

Psychometric evaluation provides some support for the use of the AIMS2 as a clinical outcome in treatment studies. As noted above, administrative burden may limit its clinical use.

Research usability.

Psychometric evaluation provides support for the use of the AIMS2 in research with the caveats noted above.

ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES

Description

Purpose.

The AIMS2-SF, first published in 1997, is a shortened version of the AIMS2 and is aimed at measuring health status in people with arthritis. The measure asks about physical functioning, pain, psychological status, and social interactions. Items assessing health perceptions, demographics, and treatment information from the AIMS2 were not included. The development work for the AIMS2-SF was in patients with rheumatoid arthritis (RA), although the measure is intended for broad use across different arthritis diagnoses (3).

Content.

Items tapping 5 core domains of the AIMS2 were included (i.e., physical functioning, symptoms, social interaction, role, and affect). These 5 core domains are used in some reports of the AIMS2-SF. However, principal components factor analyses excluded the role items and reported on a slightly different 5-factor solution than the core domains. The new domains are also reported in some studies. They are upper-extremity functioning (e.g., buttoning clothing, using a key, writing, reaching, driving), lower-extremity functioning (e.g., walking, vigorous activity, being in bed or a chair most of the day), affect (e.g., tension, nervousness, feeling a burden to others), symptoms (e.g., morning stiffness, pain), and social interaction (e.g., getting together with friends or relatives, enjoying the things you do) (3).

Number of items.

There are 26 items, including upper-extremity functioning (8 items, 2 overlap with lower-extremity functioning), lower-extremity functioning (5 items), affect (4 items), symptoms (3 items), social interaction (4 items), and role (2 items).

Response options/scale.

5-point Likert-type scale. Response options depend on the item and are either 1 (all days), 2 (most days), 3 (some days), 4 (few days), and 5 (no days), or 1 (always), 2 (very often), 3 (sometimes), 4 (almost never), and 5 (never).

Recall period for items.

The past month.

Endorsements.

There are no known endorsements.

Examples of use.

The AIMS2-SF has been used as an outcome measure in intervention studies, including exercise and self-management interventions among patients with RA and osteoarthritis (OA) (39–41).

Practical Application

How to obtain.

See Guillemin et al (3), Ren et al (42), ten Klooster et al (43), and Haarvardsholm et al (35) for how to obtain free access to AIMS2-SF items and subscale domains.

Method of administration.

Self-administered.

Scoring.

Scoring is similar to the AIMS2. Some items are reverse scaled and require recoding prior to scoring. Scores for the different domains are summed and can then be converted to a range of 0–10.

Score interpretation.

Higher scores indicate poorer health. No cut off or normative values are available.

Respondent burden.

Approximately 10 minutes to complete. The questions are not burdensome in terms of the reading level required or their emotional content.

Administrative burden.

Scoring by hand takes approximately 10 minutes; computerized scoring can be completed in seconds. Minimal training required.

Translations/adaptations.

Languages available include English, French, German, Dutch, Persian, and Russian.

Psychometric Information

Method of development.

The number of items in the measure was reduced from the AIMS2 using a Delphi technique with both patients with RA (n = 12) and experts (i.e., rheumatologists, rehabilitation specialists, and methodology experts, n = 19). Patients and experts reached consensus on items critical to the scale concepts and used information from item analysis as a guide. The reduced scale was submitted to principal components analysis to examine the resulting conceptual components and to compare with the AIMS2. Data for psychometric analysis were drawn from a cohort study of 127 patients with RA (3).

Acceptability.

The AIMS2-SF is easy and relatively quick to complete. In general, missing data are not reported as a problem with the exception of the role subscale (e.g., in samples with unemployed, disabled, or retired participants). Depending on the joints affected, some floor and ceiling effects have been found, especially in the physical function subscales (i.e., upper- and lower-extremity functioning) (42, 44, 45). The AIMS2-SF has been identified for potential inclusion as a core set measure for OA (46).

Reliability.

Using the AIMS2-SF in samples of RA and OA, internal consistency using Cronbach's alpha coefficients has been good, often ranging from 0.75–0.87. Exceptions have been the social interaction subscale (ranging from 0.32–0.67) and some studies using the role subscale (3, 42, 44, 45, 47). Test–retest correlations also have been favorable with intraclass correlations over 2 days to 1 month exceeding 0.80, although lower correlations have been found for the affect and social interaction subscales (3, 44, 45, 47).

Validity.

Similar to the AIMS2, the content of the AIMS2-SF, focuses mainly on function and basic tasks of daily living. Little attention is given to disability with instrumental activities or social roles. In general, the AIMS2-SF and AIMS2 had comparable criterion validity with other measures of disability and health status (e.g., modified Health Assessment Questionnaire [MHAQ], Short Form 36 [SF-36], Western Ontario and McMaster Universities OA Index, Disease Activity Score in 28 joints). The physical function subscales of the AIMS2-SF also demonstrate reasonable construct validity and has been found to be significantly associated with greater pain, medication use, lost work days, disease symptoms like joint stiffness, tender joint count, and swollen joint count, and patient and physician global health assessments (3, 42, 44, 45, 47). Inconsistent factor structures point to the need for additional testing of subscales in samples with RA and OA (3, 42).

Ability to detect change.

Additional research is needed using the AIMS2-SF, although preliminary indications suggest no differences between the AIMS2 and AIMS2-SF in responsiveness and comparability to the SF-36 and MHAQ (3, 35). Guillemin et al report that the 3-month sensitivity to change was similar to the AIMS2, with the standardized response means at 3 months being high in the physical function and symptom subscales (3). Research by Taal et al also found similar sensitivity to change in the physical function, symptom, and affect components of the AIMS2-SF and the AIMS2 (but less responsiveness in the social interaction and role components). The physical function and symptom components of the AIMS2-SF were more sensitive to change than the MHAQ and visual analog scale (pain) measures (37). The AIMS2-SF has been used as an outcome in an exercise program and self-management intervention (40, 41). No significant changes in AIMS2-SF were found. It is not clear whether the measure was not sensitive to change or whether the intervention did not result in meaningful change.

Critical Appraisal of Overall Value to the Rheumatology Community

Strengths.

The AIMS2-SF has been shown to have similar psychometric properties as the AIMS2 with the additional benefit of being much shorter. It has recently been identified as a potentially important core measure for assessment of OA disability (46) and has been used in several European intervention studies.

Caveats and cautions.

As a disease-specific measure, the AIMS2-SF is limited in its potential for use in comparative disease studies. Different factor loadings and structures may occur when applying the AIMS2-SF to samples of RA and OA patients. Some items may load on more than one factor (e.g., both lower- and upper-extremity functioning). Studies have varied in their use of the role component of the AIMS2-SF. Other measures of work disability and role participation provide more in-depth information on this aspect of disability.

Clinical usability.

Psychometric evaluation provides some support for the use of the AIMS2 as a clinical outcome in treatment and intervention studies. However, more research is needed to determine its usefulness as a measure to guide clinical decision making at point of contact with patients.

Research usability.

Psychometric evaluation provides support for the use of the AIMS2 in research with the caveats noted above.

THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES

Description

Purpose.

The OECD measure of disability was among the first international efforts to assess the impact of ill health on tasks and activities. It was developed in 1981 to facilitate international comparisons of disability and monitor changes in disability over time across a range of health conditions. Its emphasis is on measuring long-term disruptions to normal activities. Subsequent World Health Organization (WHO) disability questionnaires were based on items from the OECD (48).

Content.

Items are combined to assess limitations in activities related to daily living. Various dimensions are covered, including eyesight (e.g., is your eyesight good enough to read ordinary newspaper print), hearing (e.g., can you hear what is said in normal conversation with 3 or 4 other persons), speech (e.g., can you speak without difficulty), upper mobility (e.g., can you carry an object of 5 kilos for 10 meters, can you cut your own food), lower-extremity functioning (e.g., can you walk up and down one flight of stairs without resting), mobility (e.g., walking 400 meters, running 100 meters), and daily activities (e.g., can you dress and undress, can you get in and out of bed).

Number of items.

The full measure includes 16 questions. An abbreviated, core set version includes 10 items.

Response options/scale.

Responses are on a 4-level scale: yes (without difficulty), yes (with minor difficulty), yes (with major difficulty), and no (not able to do).

Recall period for items.

Respondents are asked what they are able to do on a normal day.

Endorsements.

There are no known endorsements. The OECD LTD Questionnaire has been supplanted by newer measures (e.g., WHO Disability Assessment Schedule II).

Examples of use.

Although the OECD LTD Questionnaire has been largely supplanted by other disability measures, it is worth noting that the scale or some of its items have been used by a number of OECD countries in national population health surveys, including in France, Japan, Germany, the US, and Canada. For example, recent Canadian population health disability surveys used several OECD LTD Questionnaire items. The OECD LTD Questionnaire is recognized as an early precursor to other instruments like the European Quality of Life and the WHO Quality of Life (WHOQOL) questionnaires.

Practical Application

How to obtain.

A copy of the questions is available in reference (49).

Method of administration.

Questions can be interviewer administered or self-administered.

Scoring.

Scoring instructions were unavailable. However, some studies treated each item separately (i.e., did not combine them) or created a summary total of the number of areas with at least some disability by counting items where respondents indicated they had at least some difficulty performing the activity (48).

Score interpretation.

No standard scoring availability. Higher levels or counts reflect greater disability.

Respondent burden.

Items can be completed in less than 10 minutes.

Administrative burden.

The items are simple to administer. However, detailed information on scoring is not available.

Translations/adaptations.

English, Dutch, Finnish, French, German, and Japanese. It is not clear whether the OECD LTD Questionnaire has been translated into additional languages.

Psychometric Information

Method of development.

Eight countries (Canada, Finland, France, Federal Republic of Germany, The Netherlands, Switzerland, UK, and US) along with the WHO participated in a common development effort aimed at creating a “Healthfulness of Life” core set of questions. The result was the 16-item OECD Questionnaire. It is unclear whether patients were involved. Item response theory was not used in development of the questions.

Acceptability.

Floor effects are not uncommon in those under 65 years of age, with many people reporting no difficulty with any of the activities.

Reliability.

Test–retest reliability using an 11-item OECD LTD Questionnaire was low with a 2-week interval. Agreement was only between 30–70%. Although a substantial percentage (∼50%) of interviews used proxy respondents, further analyses determined that inconsistencies were not due to proxy respondents ([50] as cited in [49]).

Validity.

Although the OECD LTD Questionnaire appears to have reasonable face validity, very little systematic validity testing has been carried out on the measure. Canadian data found low to moderate correlations with rehabilitation patients completing the OECD LTD Questionnaire compared to physician mobility ratings, which are only relevant to a small part of the scale items. Correlations ranged from 0.14–0.54 (49). Wijilhuizen and Ooijendijk reported similar findings among Dutch patients (48). Other Canadian studies have looked at the construct validity of selected OECD items in samples of people with arthritis, finding that greater difficulty with OECD items was significantly associated with dependence (i.e., assistance from others) and work disability (51–55).

Ability to detect change.

Because the original purpose of the measure was to generate profiles of disability levels in the general population, the OECD LTD Questionnaire has largely not been used to examine change. McDowell cites some sensitivity results for different medical conditions ranging from 61–85%, with the highest sensitivity among those with vision, hearing, and speech problems (49).

Critical Appraisal of Overall Value to the Rheumatology Community

Strengths.

The OECD LTD Questionnaire is considered an early attempt to develop internationally applicable disability items. The WHOQOL and EQ-5D are later examples. Although the OECD LTD Questionnaire items are not used as a single measure, individual items continue to be used in some national population studies applicable to arthritis.

Caveats and cautions.

The OECD LTD Questionnaire has largely been supplanted by other disability measures.

Clinical usability.

The OECD LTD Questionnaire has been supplanted by other disability measures and should not be used in clinical evaluations.

Research usability.

Individual items continue to be used in some population health surveys. However, there may be wording variations and the items are not used as a single measure.

EQ-5D

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES

Description

Purpose.

The EQ-5D is a generic measure of health status for use in clinical, population, and economic appraisals with adult samples. The measure was developed by the European Quality of Life Group (EuroQol) to act as a core set of items for use in international studies measuring health-related quality of life across a wide range of health conditions and treatments. It provides a simple descriptive profile and single index values of health status. An early measure was first published in 1990 (56) and later finalized as the EQ-5D (57, 58).

Content.

The EQ-5D has 2 components. A descriptive system (EQ-5D descriptive system) uses single items to assess disability with 5 dimensions: mobility, self-care, usual activities (e.g., work, study, housework, family, or leisure activities), pain/discomfort, and anxiety/depression. In addition, a single visual analog scale (EQ-5D VAS) assesses self-rated health with end points labeled “Best imaginable health” and “Worst imaginable health.”

Number of items.

6.

Response options/scale.

For each item in the EQ-5D descriptive system, there are 3 levels of response: 1 = no problems (e.g., “I have no problems in walking about,” “I have no problems with performing my usual activities,” “I have no pain or discomfort”), 2 = some problems (e.g., “I have some problems washing or dressing myself,” “I am moderately anxious or depressed”), and 3 = extreme problems (e.g., “I am confined to bed,” “I am unable to wash or dress myself,” “I am unable to perform my usual activities,” “I have extreme pain or discomfort,” “I am extremely anxious or depressed”) (56–59). EQ-5D VAS scores range from 0 (worst imaginable health state) to 100 (best imaginable health state).

Recall period for items.

Today.

Endorsements.

There are no known endorsements.

Examples of use.

The EQ-5D has been used in a large number of studies across samples with diverse health conditions, as well as population studies (the EuroQol web site reports over 2,200 studies using EQ-5D as of the end of 2010). It has been applied to studies of rheumatoid arthritis (RA) (57, 58), osteoarthritis (OA) (60–62), ankylosing spondylitis (63, 64), gout (65), juvenile idiopathic arthritis (66), chronic low back pain (67, 68), systemic lupus erythematosus (69), and fibromyalgia (70). The EQ-5D has also been used in treatment and intervention studies with psoriatic arthritis (71), RA (72–75), OA (76, 77), ankylosing spondylitis (78–80), juvenile idiopathic arthritis (81), total hip/knee replacement surgery (62, 82, 83), and knee pain (84).

Practical Application

How to obtain.

Those using the EQ-5D are asked to register their research online. A copy of the questions and User Guide is available at URL: www.euroqol.org. In terms of cost, whether licensing fees exists is determined by the EuroQol Executive Office and is based on information provided by users (e.g., type of study, sample size, requested languages).

Method of administration.

The EQ-5D was designed to be easily self-administered. It can also be interviewer administered face-to-face or by telephone. A proxy version is available as well as a web-based, tablet, and PDA version.

Scoring.

Individual profiles are created using the 5 dimensions of the EQ-5D and are called the EQ-5D Health State. For example, a score of 11222 would indicate no difficulties with mobility and self care, but some/moderate problems with usual activities, pain/discomfort, and anxiety/depression. Individual scores can be converted into a summary called the EQ-5D Index. The EQ-5D Index uses a utility-weighted scoring system that has been derived from extensive studies with different countries or by taking into account an individual's own preferences as reflected in the VAS rating scale from 0–100. A constant is also subtracted if one or more dimensions are scored at 2 or 3, and a further constant if one or more dimensions are scored at 3. A negative score is possible in creating the EQ-5D Index, representing a state “worse than death.” The EQ-5D was developed using health economics principles. The EuroQol web site provides information on weights derived from EQ-5D VAS scores, as well as weights derived from time trade-off valuation techniques. EQ-5D VAS scores can be converted into quality-adjusted life year (QALY) calculations for economic analyses. Weights have been derived for over 14 countries, with additional weights in development.

Score interpretation.

Descriptive patterns for the EQ-5D Health State can result in 243 (i.e., 35) possible disability combinations ranging from 11111 to 33333. Weighted scores for the EQ-5D Index indicate 1.0 = the best imaginable health state, 0 = death, as well as negative scores representing a state “worse than death” (22). VAS scores range from 0 (worst imaginable health state) to 100 (best imaginable health state). Researchers have noted that, depending on the item weights and algorithms, widely differing QALY gains and cost-effectiveness estimations may result (84, 85–94). Where possible, researchers should use the algorithms specific to their country by consulting the EuroQol web site.

Respondent burden.

The EQ-5D was designed to be extremely brief and can be completed in less than 2 minutes. Items are easy to understand and emotional sensitivity of topics is low.

Administrative burden.

Time and training are needed to score the EQ-5D. The EuroQol web site must be consulted to register studies and to determine the appropriate rates for a country.

Translations/adaptations.

An EQ-5D-Y is available for children (95). More than 120 translations of the EQ-5D exist. Examples of languages include Dutch (and Dutch for Belgium), English (and English for Australia, Canada, New Zealand, UK, US, Singapore, and South Africa), Finnish, French (and French for Belgium, Canada, and Switzerland), German (and German for Austria and Switzerland), Norwegian, Swedish, Spanish (and Spanish for Argentina, Chile, Columbia, Costa Rica, Guatemala, Mexico, Peru, US, Uruguay, and Venezuela), Afrikaans, Indonesian, Bulgarian, Italian, Cantonese for Hong Kong, Japanese, Catalan, Estonian, Latvian, Chinese (and Chinese for Singapore and Taiwan), Lithuanian, Malay, Croatian, Polish, Czech, Portuguese (and Portuguese for Brazil), Danish, Romanian, Russian (and Russian for Israel), Greek, Thai, Hebrew, Slovakian, Turkish, Hungarian, and Slovenian.

Psychometric Information

Method of development.

Although originally created by EuroQol beginning in 1987, membership has grown to include members from North America, Asia, Africa, Australia, and New Zealand. The goal of the measure was to create an easy-to-administer core set of items for use in international studies across a wide range of health conditions and treatments. The dimensions were selected after a detailed examination of existing health status measures, including the Quality of Well-Being Scale, Sickness Impact Profile, Nottingham Health Profile, and Rosser Index. The number of health states in each dimension was deliberately kept to a minimum so that the measure could easily be administered and used for decision making.

Acceptability.

Reports of missing data are variable. In testing the original EuroQol questionnaire, missing data were reported as much as 40% in the UK sample (56). Another study using the EQ-5D reported less than 1% missing data among returned questionnaires (64). The most frequently omitted items were pain/discomfort and anxiety/depression. Floor effects are not unusual in general populations, with individuals reporting 11111 (i.e., no problems) (22). Among patients with ankylosing spondylitis, floor effects in the 5 dimensions ranged from 10.4% (pain/discomfort) to 61.7% (self-care) and ceiling effects ranged from <1% (mobility) to 20.2% (pain) (64).

Reliability.

Test–retest reliability for the EQ-5D Index ranges from intraclass correlation coefficient (ICC) 0.64–0.78 in samples ranging from 1 week to 3 months (58, 96). ICC values for the EQ-5D VAS ranged from 0.70–0.85 (58). Gamma coefficients ranged from 0.57–0.80. In a sample of 82 people with knee OA measured twice over a 1-week period, ICC for the EQ-5D Index was 0.70 (95% confidence interval [95% CI] 0.58–0.80) and was 0.73 (95% CI 0.61–0.82) for the EQ-5D VAS (60). Comparing telephone and face-to-face interviews in a sample of older adults, McPhail and colleagues found moderate to high levels of agreement. ICC values were 0.82 for EQ-5D Index scores and 0.58 for the EQ-5D VAS (item kappas ranged 0.67–0.83) (97).

Validity.

In studies of patients with RA, the EQ-5D Index was significantly associated with Health Assessment Questionnaire (HAQ), depression, and anxiety. EQ-5D VAS scores were significantly associated with HAQ, self-assessed joint pain, and depression (57, 58). Among patients with knee OA, the EQ-5D Index correlated with arthritis duration and greater Western Ontario and McMaster Universities OA Index and Short Form 36 scores, but lacked discriminative ability among those with moderate disability (60). Similarly, in a study of patients with psoriatic arthritis, the EQ-5D Index did not discriminate well among patients with and without disability compared to the Psoriatic Arthritis Quality of Life questionnaire and HAQ (98). Some authors have argued that the EQ-5D lacks dimensions such as dexterity, social functioning, and vitality that are important to disability and that might be responsible for observed gaps in the distribution of EQ-5D Index scores, especially in the midutility range (between 0.30 and 0.5; results in bimodal distributions of scores) (99). This may also be responsible for the ceiling and floor effects noted in a number of studies. Response options and algorithms used to create QALYs have been noted as problematic in a number of studies (70, 85–93, 100).

Ability to detect change.

The EQ-5D has rarely been used as a primary outcome in intervention studies, making it difficult to evaluate its appropriateness to detect change. Cut off points have been suggested for the EQ-5D to identify acceptable health status for RA patients (101). Specifically, the patient acceptable symptom state cut point with 80% specificity was estimated to be 0.70 in the EQ-5D Index. The cut point was 0.65 when the 75th percentile was used. Minimal clinically important improvement cut points assessed by 80% specificity varied from 0.10–0.19 in the EQ-5D Index. In a sample of patients with RA, the EQ-5D Index was found to be significantly associated with changes in HAQ pain, joint pain, depression, and anxiety over 3 months (58). Other studies have found no changes in EQ-5D utility scores in treatment of patients with RA (72). Among patients with ankylosing spondylitis, responsiveness was found to be weak for the EQ-5D Index, but good for the VAS (64).

Critical Appraisal of Overall Value to the Rheumatology Community

Strengths.

It is quick and easy to develop an EQ-5D Health State profile. The EQ-5D has been used in a number of studies with arthritis populations. It allows comparison to other conditions and allows for economic evaluations.

Caveats and cautions.

Scoring is complex for the EQ-5D Index. Some authors have argued that there are important dimensions missing and a bimodal distribution of scores may compromise the validity of the measure and its ability to detect change. Researchers have noted that, depending on the item weights and algorithms, widely different QALY gains and cost-effectiveness estimations may result.

Clinical usability.

The EQ-5D has been used in clinical settings. It is easy and quick to generate an individual patient profile. However, the measure is not detailed enough to use as a clinical decision making tool.

Research usability.

May be useful as core variable to describe populations, but does not provide a lot of detail.

WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES

Description

Purpose.

The WHODASII measures disablement by assessing a range of activity limitations and participation restrictions. It can be used for community health studies, population surveillance, or clinical assessments. The WHODASII is a generic measure that does not target a specific disease but can be used to compare individuals with difficulties stemming from disease, illness, injury, and mental, emotional, or substance abuse problems. The measure was first published in 2000. We used the version published on the WHO web site in 2010 for this review.

Content.

Six domains are assessed: cognition (i.e., understanding or communicating, understanding what people say, concentration, remembering, starting a conversation), mobility (i.e., getting around, standing for long periods, moving around the home, getting out of your home, walking a kilometer), self-care (i.e., washing your whole body, getting dressed, eating, staying by yourself for a few days), getting along with people (i.e., maintaining a friendship, getting along with those close to you, making new friends, sexual activities), life activities (i.e., household work, employment, school activities), and participation (i.e., joining in community activities, barriers or hindrances in world around you, living with dignity, taking care of health, emotional impact of health).

Number of items.

The 36-item version of the WHODASII includes cognition (6 items), mobility (5 items), self-care (4 items), getting along with people (5 items), life activities: household (4 items), life activities: work or school (4 items), and participation (8 items). Seven additional items in the life activities and participation domains are asked of individuals reporting any difficulties with activities. These items ask about the number of days health problems resulted in missing, reducing time with, or slowing down activities and roles.

Response options/scale.

Questions are assessed on a 5-point Likert-type scale, where 1 = none, 2 = mild, 3 = moderate, 4 = severe, and 5 = extreme or cannot do.

Recall period for items.

The past 30 days.

Endorsements.

Endorsed by the WHO.

Examples of use.

The WHODASII has been used in a large number of studies with diverse samples. It has been administered in population and community health surveillance studies, as part of clinical assessments, and in intervention research. In arthritis, the WHODASII has been applied to samples of rheumatoid arthritis (RA), osteoarthritis (OA), scleroderma, and ankylosing spondylitis (102, 103).

Practical Application

How to obtain.

Available from the WHO web site: http://www.who.int/icidh/whodas/instrument_download.html. There is no cost to the user. Users must register to use the WHODASII.

Method of administration.

An interviewer-administered questionnaire is available for the 36-item, 12-item, and 12 + 24 item WHODASII (see translations/adaptations section for additional information about these versions). The self-administered WHODASII is available in the 36-item and 12-item format. A proxy version of the WHODASII can be completed by others, including clinicians. Also available in 36-item and 6-item versions.

Scoring.

Detailed scoring information and updates are available to those who access the WHODASII web site and register their study. In general, total and subscale (i.e., domain) scores are based upon a weighted sum of items and then transformed into a standard scale (0–100). Scores for those working or in school are based on all 36 items. Scores for those not working or in school are based on 32 items (i.e., omitting the work/school questions of the life activities domain). Mean scores can be used to assign a value for missing data. Simple scoring (i.e., summing scores for each domain/no weighting) can be calculated to facilitate use in the clinic, but should not be used to compare with other samples. Complex scoring using item response theory is available on the WHO web site.

Score interpretation.

Transformed scores range from 0–100 with higher scores indicating greater disability (i.e., more activity limitations and participation restrictions).

Respondent burden.

The 36-item version takes ∼20 minutes to complete. The 12-item version takes ∼5 minutes. Written and verbal prompts are provided to help respondents, and the interviewer-administered version can aid participants with literacy and other difficulties completing the questionnaire. A proxy version is also available. The questionnaire is not burdensome in terms of reading level required or emotional content.

Administrative burden.

Some training is required for the interviewer-administered questionnaire. A detailed training manual is available that facilitates training. Scoring difficulty is moderate.

Translations/adaptations.

A 12-item brief assessment of the WHODASII includes 1 or 2 items from each of the domains in the 36-item version plus 3 global questions asking about number of days with health difficulties in past 30 days, number of days of being unable to carry out usual activities, and number of days for which activities were cut back or reduced. A 12 + 24-item screener is available in an interviewer-administered format. This version asks 12 items to screen for disability. If respondents indicate any difficulties, they are asked up to 24 additional questions according to the interviewer guide. Languages available include Albanian, Arabic, Bengali, Chinese (Mandarin), Croatian, Czech, Danish, Dutch, English, Finnish, French, German, Greek, Hindi, Italian, Japanese, Kannada, Korean, Norwegian, Portuguese, Romanian, Russian, Serbian, Slovenian, Spanish, Sinhala, Swedish, Tamil, Thai, Turkish, and Yoruba. The WHO is active in updating and adapting the WHODASII.

Psychometric Information

Method of development.

The WHODASII was developed in collaboration with the WHO, National Institute on Mental Health, National Institute on Alcohol Abuse and Alcoholism, and National Institute on Drug Abuse. Collectively, they make up the WHO Classification, Terminology and Standards team. Development included a 19-country cross-cultural sample for psychometric analysis and screening. Field testing occurred in 2 waves and included members of the general population in good health, people with physical disorders/conditions, people with mental or emotional disorders, and people with problems related to alcohol or drug use (104, 105). Psychometric analyses included confirmatory factor analysis, nonparametric, and parametric methods of item response theory testing (104, 106–108).

Acceptability.

Overall, missing data are low. However, questions related to employment, school, and sexual activities have higher amounts of missing data or refusal rates. Floor effects (i.e., no problems) have been found most frequently in the domains measuring self-care and getting along with others (106–108).

Reliability.

Internal consistency of the total or global WHODASII using Cronbach's alpha coefficients is often in the range of 0.86–0.95 for the interviewer-administered and self-administered 36-item versions (102, 105–108). Internal consistency across the different domains of the WHODASII often exceed 0.85, although Cronbach's alpha levels have sometimes been much lower for the following domains: getting along with others (often below 0.75) and self-care (0.69–0.82) (102, 107, 108). Test–retest intraclass correlations across domains and using the total scale have typically been high (e.g., 0.82–0.96 in a sample of individuals with scleroderma when administered after 1 week [102]; 0.87–0.97 in a sample of individuals with knee OA [107]).

Validity.

The WHODASII has undergone extensive psychometric analyses including confirmatory factor analysis, nonparametric, and parametric methods of item response theory testing (104, 106–109) in samples of individuals with diverse health conditions, including rheumatic diseases and musculoskeletal disorders. Data for arthritis has often been combined with those of other diseases and not presented separately. However, criterion, construct, and discriminant validity for the WHODASII in samples with different types of arthritis have been good to excellent (102, 103, 105–111). For example, domain and total scores have significantly correlated with clinical disease features (e.g., tender and swollen joint counts, pain, fatigue), other measures of disability and functioning (e.g., Short Form 36, Disease Activity Score in 28 joints, Health Assessment Questionnaire disability index, Western Ontario and McMaster Universities OA Index, Nottingham Health Profile), and have discriminated between pain and disease severity groups (102, 103, 107–111).

Ability to detect change.

Research by the WHO examining the predictive validity and sensitivity to change of the WHODASII is ongoing. Research examining responsiveness and sensitivity to change in samples with arthritis is lacking. However, in a study examining a rehabilitation intervention with different disease groups that included RA and OA, there were small to modest effect sizes ranging from 0.16–0.69 found (108). Similar effect sizes were found in a 3-week spa intervention with individuals with ankylosing spondylitis (103).

Critical Appraisal of Overall Value to the Rheumatology Community

Strengths.

Emerging psychometric work using WHODASII across a range of arthritis diagnoses is promising. WHODASII is actively being tested in a variety of countries making its use in international, comparative studies promising. The measure captures a range of elements important to arthritis.

Caveats and cautions.

More data are needed using samples of patients with arthritis, especially to examine responsiveness to change. Because not all domains of the WHODASII are equally relevant to all diseases, there may be floor effects in some areas (e.g., cognition).

Clinical usability.

Additional data are needed to support use of WHODASII in clinical and treatment settings. The wide range of versions available (e.g., 36 item, 12 item) suggest that administrative burden in the clinic should not be a problem.

Research usability.

Initial psychometric evaluation of the WHODASII and its potential for use in international, comparative studies provides support for its use in research. Additional research with different versions of the questions would be beneficial.

LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES

Description

Purpose.

The LLFDI is a general measure of physical disablement developed for older adults. It can be used across a wide range of health levels and conditions and has been applied to samples of middle-aged and even younger adults. First published in 2002, the LLFDI was revised to create an abbreviated version in 2005 and a computer-adapted version in 2008 (112–115). The abbreviated version of the LLFDI is presented elsewhere in this article.

Content.

Physical disablement is measured with questions about personal maintenance; mobility and travel; exchange of information; social, community, and civic activities; home life; paid or volunteer work; and involvement in economic activities. These are divided into 2 components: function (difficulty with basic tasks involving lower-extremity function [e.g., walking, climbing stairs, sitting down and standing up, running short and longer distances, getting in and out of a car/taxi] and upper-extremity function [e.g., using utensils, reaching overhead, putting on and taking off a coat or jacket]) and disability (measures the frequency as well as limitations in activities and roles like visiting friends and family, providing care to others, volunteer work, household chores, fitness activities, errands, and personal care needs).

Number of items.

In total, the LLFDI has 64 items. Eight additional questions are asked of individuals who use a cane, walker, or other walking device, bringing the total to 72 questions. Within the function subscale, there are questions assessing upper-extremity function (7 items), basic lower-extremity function (14 items), and advanced lower-extremity function (11 items). The disability subscale assesses 16 activities/roles. For each activity/role, respondents are asked to indicate how frequently they perform the activity and to what extent they feel limited in their performance. Frequency questions assess social roles (9 items) and personal roles (7 items), and limitation questions assess instrumental roles (12 items) and management roles (4 items).

Response options/scale.

Function questions ask about difficulty with tasks and are measured on a 5-point Likert-type scale, where 1 = cannot do, 2 = quite a lot, 3 = some, 4 = a little, and 5 = none. Disability questions ask “how often do you …” with responses on a 5-point Likert-type scale, where 1 = never, 2 = almost never, 3 = once in awhile, 4 = often, and 5 = very often. Activities are also responded to in terms of “to what extent do you feel limited in …” with responses on a 5-point scale, where 1 = completely, 2 = a lot, 3 = somewhat, 4 = a little, and 5 = not at all.

Recall period for items.

A typical or average day.

Endorsements.

There are no known endorsements.

Examples of use.

The LLFDI has been used with older adults across a range of health conditions including osteoarthritis, multiple sclerosis, stroke, heart disease, cancer, urinary incontinence, rehabilitation studies, and general population studies of older adults. The measure has also been used as a screening tool, to describe the impact of various health conditions, and as an outcome in intervention studies such as physical activity and health care service interventions (116–121).

Practical Application

How to obtain.

The LLFDI can be used with permission by consulting its developer, Alan Jette, e-mail: ajette@bu.edu. Copyright is held by Boston University. Information on costs was unavailable.

Method of administration.

The original LLFDI was developed as an interviewer-administered questionnaire (113). However, self-administered (122, 123) and telephone-administered formats have also been used and a computerized adaptive test (CAT) has been developed (114).

Scoring.

Total scores can be obtained for both the function and disability components. Items are summed and then transformed to create a score ranging from 0–100, where 0 indicates poor ability (i.e., greater difficulty and more limitations) and infrequent performance, and 100 indicates good function and ability (i.e., less difficulty and fewer limitations) and frequent activity performance. Computer scoring is available. Some alternative scoring options exist for the function and disability components of the LLFDI and were based upon factor analyses and Rasch scaling techniques (113). Factor analyses of the items in the function component yielded 3 subscales measuring upper-extremity function (7 items; e.g., reaching, holding a glass, using utensils), basic lower-extremity function (14 items; e.g., climbing stairs, bending overhead, making a bed, getting on/off a bus), and advanced lower-extremity function (11 items; e.g., carrying while climbing stairs, hiking, getting up off the floor, walking a brisk mile, running to catch a bus). Factor analyses of the disability component measuring frequency of activities yielded 2 subscales measuring social roles (9 items; e.g., inviting family and friends into home, traveling out of town, keeping in touch with others, going out to public places, active recreation) and personal roles (7 items; e.g., errands, meal preparation, personal care needs, taking care of household business). Factor analyses of limitation items also yielded 2 factors of different items tapping instrumental roles (12 items; e.g., taking care of the inside of home, errands, socializing, meal preparation) and management roles (4 items; e.g., taking care of health, taking care of household business, keeping in touch with others). Rasch scaling analyses supported both the 1- and 2-factor solutions as reasonable hierarchical scales.

Score interpretation.

0–100, where 0 indicates poor ability (i.e., greater difficulty and more limitations) and infrequent performance, and 100 indicates good function and ability (i.e., less difficulty and fewer limitations) and frequent activity performance. Normative values are not available.

Respondent burden.

Takes ∼20–25 minutes to complete. The LLFDI is a lengthy questionnaire, but not burdensome in terms of reading level required or emotional content. The computer-assisted version is considerably quicker and algorithms enable items to be skipped based on answers to previous questions.

Administrative burden.

Some interviewer training is needed for interviewer-administered questionnaires. Scoring is relatively simple.

Translations/adaptations.

Available in English, German, and Hebrew.

Psychometric Information

Method of development.

Items were generated and refined based on a review of the literature, consultation with experts, and input from community focus groups with older adults. Further refinements of the LLFDI were made and subscales developed using exploratory factor analysis and Rasch analysis (112, 113).

Acceptability.

The LLFDI is relatively easy to complete. To date, studies report no or minimal floor and ceiling effects. Interviewer-administered questionnaires have resulted in little in the way of missing data (112, 113, 123–125).

Reliability.

For the function component of the LLFDI, evidence for test–retest reliability over 1–3 weeks (average 12 days) has been very good across different samples of older adults. Intraclass correlations have ranged from 0.77–0.98. Internal consistency, using Cronbach's alpha, for the 3 subscales of advanced lower-extremity function, basic lower-extremity function, and upper-extremity function were 0.96, 0.96, and 0.86, respectively. A combined function scale had a Cronbach's alpha of 0.97 (112, 120, 124). For the disability component of the LLFDI, test–retest intraclass correlations across 1–3 weeks (average 12 days) have been modest to good, ranging from 0.63–0.83 (113, 120, 124). Internal consistency of the disability component subscale measuring the frequency of activities was 0.82 using Cronbach's alpha. Internal consistency of the disability component subscale measuring limitations in activities was 0.92 using Cronbach's alpha (n = 150) (113).

Validity.

Research is needed to examine the validity of the LLFDI in samples with arthritis. However, results are promising in samples of older adults with a range of chronic health conditions. Psychometric analyses have compared scores on the function and disability components to performance tests such as 400-Meter Walk Test, Short Physical Performance Battery, 2-Minute Walk Distance, 8-Foot Walk Test, Berg Balance Scale, and Timed Up & Go Test, as well as self-report questionnaires like the physical functioning scale and physical component of the Short Form 36. (120, 122, 123, 125, 126). Results found that the LLFDI demonstrated concurrent and predictive validity with functional performance using 400-Meter Walk Test and Short Physical Performance Battery. The function component of the LLFDI demonstrated substantial associations with functional performance measures, which were strongest for the overall and lower-extremity function dimensions. With respect to predictive validity, it was found that performance measures of physical function predicted limitations in daily activities in the disability component of the LLFDI (123). Cross-sectional convergent validity of the LLFDI also was supported when applied to adults 45–65 years of age with chronic conditions (127).

Ability to detect change.

The time frame for the LLFDI is a typical or average day. Asking participants to characterize their general disability may result in difficulties in the measure's ability to detect small changes. Research also needs to be conducted in arthritis. To date, studies with older adults have used the LLFDI as an outcome in research on the use of antidepressants (118, 122) and a physical activity intervention for stroke patients (121) with the LLFDI showing significant changes as a result of treatment and intervention. Olarsch (128) reported that the LLFDI was more responsive than the EQ-5D and Elderly Mobility Scale in a group of older adults living in long-term care.

Critical Appraisal of Overall Value to the Rheumatology Community

Strengths.

The LLFDI covers a range of disability domains not found in many arthritis-specific measures, including a participation in diverse social activities and roles. It also asks participants for information about the frequency of involvement in activities and roles, as well as limitations. As a result, it is a fairly comprehensive measure with good potential for use with older adults who have a range of chronic health conditions, including arthritis.

Caveats and cautions.

Currently, there is no detailed psychometric evaluation of the measure with arthritis samples. The length of the measure may limit its use, although a CAT version of the LLFDI may enable quicker administration in some settings.

Clinical usability.

Although psychometric evaluation supports the use of the LLFDI in samples of older adults in long-term care, depressed older adults, and stroke patients, clinical research in arthritis is needed. The length of the LLFDI may be a barrier to its clinical use.

Research usability.

More research is needed in arthritis, but the LLFDI is a potentially attractive tool as its items include both activity limitations and disability with roles. The length of the LLFDI may be a barrier to its research use.

LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES

Description

Purpose.

The LLFDI-Abbreviated is a general measure of physical disablement developed for older adults. It can be used across a wide range of health levels and conditions. The LLFDI-Abbreviated was created in 2005 (115).

Content.

The 2 components of the original LLFDI were maintained with disablement measured with questions about function and disability. The function component maintained separate subscales related to upper-extremity function (e.g., holding a glass of water, using utensils, unscrewing a lid), basic lower-extremity function (e.g., getting in/out of a car, bending over while standing, walking around the home), and advanced lower-extremity function (e.g., carrying while climbing stairs, walking 1 mile with rests, going up/down 3 flights of stairs). Disability component items measuring frequency and limitations in activities have subscales for social (e.g., go out to public places, visit friends) and personal roles (e.g., errands, household business). It is worth noting here that the original LLFDI labeled factors derived from disability component limitation items as instrumental roles and management roles.

Number of items.

The total LLFDI-Abbreviated has 31 items. The function component has retained 15 of the original 32 items measuring upper-extremity (5 items), basic lower-extremity (5 items), and advanced lower-extremity function (5 items). The disability component retained 8 of the original 16 items (social roles = 4 items, personal roles = 4 items).

Response options/scale.

Function questions ask about difficulty with tasks and are measured on a 5-point Likert-type scale, where 1 = cannot do, 2 = quite a lot, 3 = some, 4 = a little, and 5 = none. Disability questions ask about frequency of activities (i.e., “how often do you …”) with responses on a 5-point Likert-type scale, where 1 = never, 2 = almost never, 3 = once in awhile, 4 = often, and 5 = very often. Activities are also responded to in terms of limitations (i.e., “to what extent do you feel limited in …”) with responses on a 5-point scale, where 1 = completely, 2 = a lot, 3 = somewhat, 4 = a little, and 5 = not at all.

Recall period for items.

A typical day or average day.

Endorsements.

There are no known endorsements.

Examples of use.

Community samples of adults (age ≥60), geriatric inpatients, older adults, and physical activity changes (115, 129–132).

Practical Application

How to obtain.

See information for original LLFDI. Items in the LLFDI-Abbreviated are outlined in reference (115).

Method of administration.

Psychometric testing has mostly used an interviewer-administered LLFDI-Abbreviated (115). However, a mailed, self-administered questionnaire has also been used in research (132, 133).

Scoring.

Scoring practices differ from the original LLFDI. The abbreviated version sums item scores across the function and disability subscales (115, 131). Total scores for the function and disability components can also be calculated.

Score interpretation.

Function component subscales (i.e., upper extremity, basic lower extremity, advanced lower extremity) range from 5–25. Total scores range from 15–75. Higher scores indicate fewer functional limitations (i.e., less disability). Disability component subscales (i.e., social and personal roles) range from 4–20. Total scores range from 8–40. Higher scores indicate less disability. No cut points or normative values have been established.

Respondent burden.

Time to complete ranged from under 10 minutes to ∼30 minutes in a sample of older community-dwelling adults (129). Questions are not burdensome in terms of reading level required or emotional content.

Administrative burden.

Some interviewer training is needed for interviewer-administered questionnaires. Scoring is relatively simple.

Translations/adaptations.

Available in English and German.

Psychometric Information

Method of development.

A reduced number of items were selected from the original LLFDI using confirmatory factor analysis with maximum likelihood estimation in LISREL software used to establish model fit parameters (115).

Acceptability.

Denkinger and colleagues report minimal floor and ceiling effects in the German LLFDI-Abbreviated and a good range of scores (129, 130).

Reliability.

Test–retest reliability for the LLFDI-Abbreviated function component was very good (0.81–0.96) and interrater reliability was acceptable to very good (0.62–0.96) with the German LLFDI-Abbreviated (129). No information about test–retest reliability was available for the disability component. Internal consistency as measured by Cronbach's alpha ranged from: upper-extremity function 0.58–0.84; basic lower-extremity function 0.76–0.83; and advanced lower-extremity function 0.80–0.86 (115, 129, 130). Cronbach's alphas for the disability component subscales of the LLFDI-Abbreviated were lower, especially for items asking about the frequency of social role activities (alphas ranged from 0.38–0.67). Cronbach's alphas for the personal role subscales were better (alphas ranged from 0.77–0.83). Items asking about limitations in social and personal roles ranged from 0.77–0.83 (115).

Validity.

The original LLFDI and LLFDI-Abbreviated were moderately to highly correlated with one another. The relationship between the function component subscales on the 2 versions ranged from 0.92–0.97 and the relationship between the 2 versions of the disability component subscales ranged from 0.76–0.80 (115). The LLFDI-Abbreviated subscales were significantly associated with performance tests such as the Physical Activity Scale for the Elderly and the Community Healthy Activities Model Program for Seniors. Correlations were typically greater for the function component subscales compared to the disability component (115). In a sample of 292 adults with multiple sclerosis ranging in age from 20–69 years (mean age 48 years), LLFDI-Abbreviated components were moderately to highly related to neurological impairments and symptoms, as well as poorer health status and quality of life in the expected directions (133). The function component score also was found to be moderately to highly correlated with the Fall Efficacy Scale International, the Short Physical Performance Battery, the Timed Up & Go Test, and other performance-based measures (e.g. normal speed, maximum speed, step length; Spearman's correlations ranged from 0.42–0.76) (130).

Ability to detect change.

Data are limited. However, Denkinger and colleagues used standardized response mean (SRM) values to evaluate sensitivity to change across a 3-week period for the function component of the LLFDI-Abbreviated. SRM values were all significant with medium effect sizes, varying with the treatment period (130).

Critical Appraisal of Overall Value to the Rheumatology Community

Strengths.

Similar to the original version, the LLFDI-Abbreviated covers a range of disability domains not found in many arthritis-specific measures, including a participation in diverse social activities and roles. It asks participants for information about the frequency of involvement in activities and roles, as well as limitations. Its shorter length may make it useful in studies with individuals who have arthritis. Preliminary findings suggest that the measure may also be applicable to younger and middle-aged samples.

Caveats and cautions.

Additional psychometric analyses of the measure are needed to assess reliability, validity, and sensitivity to change.

Clinical usability.

More research is needed prior to a recommendation on the clinical usability of the LLFDI-Abbreviated.

Research usability.

More research is needed in arthritis, but the LLFDI-Abbreviated is a potentially attractive tool as its items include both activity limitations and disability with roles. The shorter length of this version may make it more feasible for use.

Table  . Summary Table for Disability Measures
ScalePurpose/contentMethod of administrationRespondent burdenAdministrative burdenScore interpretationReliability evidenceValidity evidenceAbility to detect changeStrengthsCautions
Arthritis Impact Measurement Scales 2 (AIMS2)Arthritis-specific health statusSelf-administeredModerate to highBy hand: moderate; by computer: lowHigh scores = poor healthGoodGoodGoodArthritis-specific; good psychometric propertiesLengthy time to complete; scope of disability questions limited; not useful for comparative disease studies
Arthritis Impact Measurement Scales 2- Short Form (AIMS2-SF)Arthritis-specific health statusSelf-administeredLowLowHigh scores = poor healthFair to goodGoodGoodArthritis-specific; time to administer is shortUsers should be aware of variability in subscales; scope of disability questions limited; not useful for comparative disease studies
Organization for Economic Cooperation and Development (OECD) Long-Term Disability Questionnaire (LTD)Cross-disease disability measure aimed at measuring long-term disruptions to normal activitiesInterviewer, self-administeredLowLowNo standard scoring availableNot availableLimitedNot designed to measure change over timePrecursor to other disability measuresHas been superseded by other physical disability measures
EQ-5DDisability-focused quality of life measureInterviewer, self-, telephone, electronic administrationLowModerate to highEQ-5D Health State is complex to create, consult EQ-5D web siteFair to goodFair to goodPoor to fairQuick and easy to administerComplex scoring; designed as broad overview measure; some validity issues
World Health Organization Disability Assessment Schedule II (WHODASII)Disablement, including activity limitations and participation restrictionsInterviewer, self-, telephone, proxy administrationVaries with version, typically low to moderateModerateHigher = more disabilityGoodGoodFair to goodUseful for comparative research; captures a range of elements important to arthritis; content goes beyond functional disabilityMore data needed for arthritis, especially responsiveness to change
Late-Life Function and Disability Instrument (LLFDI)Measure of physical disablement for older adultsInterviewer, self-, telephone (computerized adaptive test) administrationModerateModerateHigher scores = better functionFair to goodFair to goodFair, more data neededComprehensive; potential to be useful in arthritis samplesLengthy; more data needed for arthritis; time frame (i.e., typical day) may hinder ability to detect change
Late-Life Function and Disability Instrument Abbreviated (LLFDI- Abbreviated)Measure of physical disablement for older adultsInterviewer, self-administeredLowLow to moderateHigh scores = better functionFair to goodFair to goodData limitedSee Late-Life Function and Disability Instrument; quick to administerMore psychometric testing needed; timeframe (i.e., typical day) may hinder ability to detect change

REFERENCES

  1. Top of page
  2. INTRODUCTION
  3. ARTHRITIS IMPACT MEASUREMENT SCALES 2 (AIMS2)
  4. ARTHRITIS IMPACT MEASUREMENT SCALES 2-SHORT FORM (AIMS2-SF)
  5. THE ORGANIZATION FOR ECONOMIC COOPERATION AND DEVELOPMENT (OECD) LONG-TERM DISABILITY (LTD) QUESTIONNAIRE
  6. EQ-5D
  7. WORLD HEALTH ORGANIZATION DISABILITY ASSESSMENT SCHEDULE II (WHODASII)
  8. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT (LLFDI)
  9. LATE-LIFE FUNCTION AND DISABILITY INSTRUMENT-ABBREVIATED VERSION (LLFDI-ABBREVIATED)
  10. AUTHOR CONTRIBUTIONS
  11. REFERENCES
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