• Open Access

Robust data to close the gap: current vascular and maternal/newborn indicators as measures of progress in Aboriginal health in New South Wales

Authors


Correspondence to:
Dr David Peiris, The George Institute for International Health, PO Box M201, Missenden Rd, NSW 2050. Fax: +61 2 99934502; dpeiris@georgeinstitute.org.au

Abstract

Objective: Focussing on maternal/newborn health and vascular diseases, to review NSW Health's reporting, by Aboriginal status, against national performance indicators relevant to preventable chronic diseases.

Methods: We reviewed seven indicator documents and the Australian Institute of Health and Welfare Chronic Disease Indicator Database to identify national indicators. Indicators from six NSW Health reports were then compared with these national indicators to assess reporting by Aboriginal status and region.

Results: NSW Health routinely reports against six maternal/newborn indicators and fourteen vascular national indicators. Five of the former report performance by both Aboriginal status and region. Eight of the latter report by Aboriginal status, one of which (diabetes hospitalisations) also reports by region. Indicator quality and breadth was substantially limited by under-enumeration of Aboriginal status, small or potentially unrepresentative samples, inadequate longitudinal or regional data and few primary health care indicators. Notwithstanding these limitations, we found wide and persistent disparities in outcomes for Aboriginal people for all indicators in all regions.

Conclusions: NSW Health reports adequately, by Aboriginal status, for maternal/newborn health monitoring (albeit constrained by under-enumeration), but provides limited information about vascular health. A minimum, national chronic disease indicator dataset against which all jurisdictions would report performance by Aboriginal status and region is needed. Improved monitoring requires sustained efforts to address under-enumeration, better survey sampling, and population representative data from the primary care system.

Federal and State governments have pledged to close the life expectancy gap of Aboriginal and Torres Strait Islander people within a generation. Accompanying this pledge has been unprecedented financial commitment by the Council of Australian Governments (COAG)1 and major health reform proposals that could substantially influence healthcare, both in NSW and Australia.2–5 A key component of these reforms is the imperative to address Aboriginal and Torres Strait Islander health inequalities and to better measure the efficacy of Australia's healthcare systems in achieving such gains.

A primary criterion by which healthcare systems are increasingly being judged is their success in improving outcomes for vulnerable populations. In establishing a framework for success, the US Commonwealth Fund (CMWF) recommends monitoring by sound metrics for assessing whether or not strategic goals are being achieved.6 Identifying the most appropriate metrics and establishing mechanisms for the collection of high quality data are crucial for assessing the healthcare provided to Indigenous peoples. Robust mechanisms for measurement of macro-performance, which can be compared across regions and with non-Indigenous healthcare, have been identified as a key priority.7

The Aboriginal and Torres Strait Islander Health Performance Framework (A&TSI HPF) is the most comprehensive attempt yet to develop such a mechanism.8 It was established to monitor the impact of the National Strategic Framework for Aboriginal and Torres Strait Islander Health and to influence policy analyses, planning and program implementation. Drawing from the National Health Performance Committee framework,9 three tiers of indicators (each with a number of sub-dimensions) are outlined:

  • 1) health status and outcomes (health conditions, human function, life expectancy and deaths);
  • 2) determinants of health (environmental and socio-economic factors, community capacity, health behaviours and person-related factors); and
  • 3) health system performance (effective, appropriate, efficient, responsive, accessible, safe, continuous, capable and sustainable).8

In 2007, the Clinical Excellence Commission (CEC) in New South Wales (NSW) published its first ‘Chartbook’ on the quality of healthcare in NSW.10 Modelled on CMWF reports, the Chartbook provides performance snapshots on trends in several indicators. Intended to complement the NSW Chief Health Officer's (CHO) Report11 and other relevant annual reports, the Chartbook aims to monitor these trends, identify areas for further investigation and to act as a resource to facilitate change. The 2008 Chartbook12 includes a new chapter on selected outcome indicators by Aboriginal status. Review of these indicators raise three broad questions. Which national performance indicators are routinely reported against by Aboriginal status in NSW? How reliable is this information? Given the proposed national health reforms, how well-placed is NSW to monitor the effectiveness of these reforms for Aboriginal people?

We seek here to answer these questions as they relate to one health priority area, namely preventable chronic diseases (PCD). Given there are more than 400 indicators in the Australian Institute of Health and Welfare (AIHW) Chronic Disease Indicator Database (CDID),13 we focused on two priority areas:

  • 1) Maternal/newborn health because of the importance of a ‘life-course’ approach to PCD
  • 2) Vascular-related diseases (cardiovascular disease (CVD), chronic kidney disease (CKD) and diabetes) and their risk factors because these conditions make the greatest contribution to disease burden.14

Methods

This review comprised three steps.

Step 1: A review of Federal government documents outlining performance indicators by Aboriginal/ Torres Strait Islander status in maternal/newborn health and vascular diseases. We focused on ‘strategic change indicators’ that measure change in the shorter term and for which more immediate action can be taken; we therefore excluded ‘headline indicators’ related to mortality.15 We used a purposive sampling strategy to identifying indicator documents. For inclusion, documents needed to be recent (published after 2007); national in focus; relevant to preventable chronic diseases in primary care and/or hospital settings; and have explicit indicator definitions. Our search used four strategies:

  • 1A review of data sources in the A&TSI Health Performance Framework and a ‘snowballing’ search for other government and non-government documents which used these data sources
  • 2Consultation with content experts in healthcare safety and quality to identify additional documents
  • 3A keyword search for Indigenous-related indicators in the AIHW CDID
  • 4A review of the proposed indicators in the discussion documents/reports relating to the proposed national health reforms. The final indicator list was reviewed by staff from the Office of Aboriginal and Torres Strait Islander Health (OATSIH).

Step 2: A review of NSW Health documents to identify indicators which matched those identified in Step 1. We searched the NSW Health website for routinely published reports on health performance monitoring. Staff in the Clinical Excellence Commission and the NSW Centre for Epidemiology and Population Health reviewed the retrieved reports and advised on the need to include any additional reports. For the indicators identified from these documents, we examined the quality of the data collections from which they were derived, their duration of reporting and whether or not they reported by Aboriginal status and/or any one of the following regional units (Area Health Service, Local Government Area or Accessibility/Remoteness Index of Australia (ARIA+)).

Step 3: For those indicators identified above which do report by Aboriginal status, we sought to provide a snapshot of the routinely available types of information. We extracted and summarised data from the Health Outcomes Information Statistical Toolkit (HOIST), from published reports and from the Australian and New Zealand Dialysis and Transplant Registry. For maternal/ newborn health indicators, bi-variate (cross-tabular) analyses compared indicators with the results expressed as percentages by year, Aboriginal status and ARIA+. Information on vascular risk factors are expressed as weighted percentages for the Aboriginal and total population by urban and rural region. Hospitalisations and dialysis data are expressed as directly age standardised rates by year and Aboriginal status.

Results

Performance measures described within four Federal government,8,15–17 and three national health reform documents3,18–19 were reviewed. These are presented in Table 1. No additional indicators, not already included in these documents, were identified from the AIHW CDIC. Six NSW Health reports were examined for their reporting against these indicators.11,20–24 The data sources are primarily derived from three NSW data collections: the NSW Midwives Data Collection (MDC) 1994–2007, NSW Admitted Patient Data Collection (APDC) 1993/94 to 2006/07 and NSW Population Health Survey (PHS) 2002–05.Box 1 summarises the scope and methods used in those data collections and describes issues relating to data quality. Six maternal/newborn indicators and fourteen vascular disease-related indicators identified in the national documents are routinely reported against in NSW. Table 2 summarises these indicators, the duration of rep orting and whether or not they report by Aboriginal status and/or region. For those indicators routinely reported by Aboriginal status, key performance features are described below.

Table 1.  Non-mortality maternal/newborn and vascular health indicators described in national documents that recommend reporting by Indigenous status.
IndicatorHPF Tier1Reported in current documents2Proposed in health reform documents2Data sources3
  1. Notes:

  2. 1. Health Performance Framework

  3. 2. Indicator Documents

  4. A&TSI HPF: Aboriginal and Torres Strait Islander Health Performance Framework8

  5. PC OID: Productivity Commission: Overcoming Indigenous Disadvantage Report15

  6. GP NPI: Department of Health and Ageing Divisions of General Practice National Performance Indicators Program17

  7. HFL: Office of Aboriginal and Torres Strait Islander Health (OATISH): Healthy for Life Essential Indicators16

  8. CTG: Steering Committee for the Close the Gap campaign for Indigenous Health Equality18

  9. NHHRC: National Health & Hospitals Reform Commission Interim Report19

  10. NPH Strategy: National Preventive Health Taskforce National Preventive Health Strategy3

  11. 3. Data sources

  12. NPDC: National Perinatal Data Collection

  13. NHMD: National Hospital Morbidity Database

  14. NHS: National Health Survey

  15. NATSIHS: National Aboriginal and Torres Strait Islander Health Survey

  16. OSCAR: OATSIH Services Collection Analysis and Reporting (OSCAR) system

  17. SAR: Department of Health and Ageing Service Activity Reporting Database

  18. BEACH Bettering the Evaluation and Care of Health program

  19. APCC Australian Primary Care Collaboratives program

  20. ANZDATA Australian & New Zealand Dialysis and Transplant Registry

Maternal/newborn health
Mean, low, premature birth weight prevalence by maternal Indigenous status (reported by various maternal and birth characteristics)1A&TSI HPF, PC OIDNHHRCNPDC
Mean birth weight, low and high birth weight by newborn Indigenous status1HFLCTGOSCAR
Tobacco use in pregnancy2A&TSI HPF, PC OIDNHHRCNPDC
Smoking, alcohol consumption and illicit drug use at <13 weeks pregnancy and in third trimester2HFL OSCAR
Breast feeding practices2A&TSI HPFNPH StrategyNHS, NATSIHS
Timing of first antenatal visit3A&TSI HPF, PC OID, HFLCTG, NHHRCNPDC, OSCAR
Vascular health
Circulatory diseases/diabetes hospitalisations and self-reported prevalence, general practice encounters1A&TSI HPF, PC OID NHS, NATSIHS, NHMD, BEACH
Blood Pressure (BP) hospitalisations, self-reported prevalence, general practice encounters
End-stage renal disease – incidence, hospitalisation and treatment modality1A&TSI HPF ANZDATA
Smoking prevalence2A&TSI HPF, PC OIDCTG, NPH StrategyNHS, NATSIHS
Overweight and obesity prevalence
Level of physical activity2A&TSI HPFNPH StrategyNHS, NATSIHS
Sufficient daily fruit and vegetable intake    
Hospitalisations due to tobacco2PC OIDNPH Strategy 
Hospital separations attributed to obesity/tobacco
Glycosylated heamoglobin recording and control for diabetics3A&TSI HPF, GP NPI HFLNHHRCOSCAR, APCC, Medicare
Cholesterol recording and control for diabetics    
BP recording and control for coronary heart disease/diabetes HFL  
Provision of chronic care plans (Medicare items 721, 723)
Services with a documented chronic disease management strategy3A&TSI HPF, GP NPI GP NPI, SAR
Services with chronic disease registers/recall systems    
Provision of health assessments (Medicare items 704, 706, 708, 710)3GP Divisions HFL OSCAR, Medicare
Access to coronary heart disease hospital procedures3A&TSI HPF NHMD
Ambulatory care sensitive conditions – diabetes complications and angina
Provision of cardiovascular disease (CVD) risk assessments3Not reportedCTGNot stated
Access to medicine and non-medicine management for people at elevated vascular risk and/or with diabetes
Risk factor recording and control for CVD, chronic kidney disease (CKD) and diabetes (includes psychosocial risk)
Brief interventions for smokers, people with overweight/obesity3Not reportedNPH TaskforceNot stated
Diabetes receipt of an annual cycle of care3Not reportedNHHRCNot stated
Specialist access for secondary prevention of chronic disease3Not reportedCTGNot stated
Reduced time to admission and guidelines implementation for CVD, diabetes, CKD
Access to cardiac/stroke rehabilitation, dialysis and transplantation
Waiting time at 90th percentile for cardio-thoracic surgery3Not reportedNHHRCNot stated
Table 2.  Indicators reviewed from New South Wales (NSW) Department of Health Reports.
ReportsPrincipal data collection sourcesIndicatorsHPFa tierData reporting periodData routinely reported by:
     Aboriginal statusRegionbBoth Aboriginal status & region
  1. Notes:

  2. a) Health Performance Framework

  3. b) ‘Region’ is defined as reporting by any of the following: Local Government Area, Area Health Service, Accessibility/Remoteness Index of Australia

  4. c) Data not routinely reported by Aboriginal status due to small sample size

  5. d) Data for overweight/obesity and diabetes from the 2004 National Aboriginal and Torres Strait Islander survey are also reported in Two Ways Together.

  6. e) Data are reported separately for Aboriginal people based on survey respondents over the 2002–2005 period

  7. f) Australian and New Zealand Dialysis and Transplant Registry

  8. g) The population prevalence of maintenance dialysis provided for end-stage kidney disease (both peritoneal and haemodialysis). It includes hospital, satellite and community- based (home) dialysis

NSW Mothers and Babies Report23Midwives DataTeenage pregnancy11994–2007YesYesYes
 Collection (MDC)Tobacco use in pregnancy21994–2007YesYesYes
Report on child health from the NSW Population Low birth weight prevalence11994–2007YesYesYes
  Premature birth prevalence11994–2007YesYesYes
Health Survey22 Antenatal visit before 20 weeks of pregnancy31994–2007YesYesYes
The health of the people of NSW – Report of the Chief Health Officer (CHO)11NSW Population Health Survey (PHS)Duration of breast feeding up to 24 months22002–2006NocYesNo
Two Ways Together24       
Report on Adult Health21/Report on Adult AboriginalNSW PHSOverweight & obesity prevalence22002–2008dYeseYesNo
Health20 from the NSW Population Health Survey Current daily & occasional smoking22002–2008YeseYesNo
  Diabetes or high blood glucose prevalence12002–2008dYeseYesNo
  Fruit and vegetable consumption22002–2008YeseYesNo
The health of the people of NSW – Report of the CHO Physical activity in adults22002–2008YeseYesNo
  Cardiovascular risk factors by diabetes status22006–2007NoNoNo
The health of the people of NSW – Report of the CHOAdmitted Patient Data CollectionCardiovascular disease hospitalisations11994–2007YesYesNo
Two Ways Together(APDC)Stroke hospitalisations11994–2007NoYesNo
  Diabetes hospitalisations11994–2007YesYesYes
  Type of ambulatory care sensitive conditions31994–2007NoYesNo
  Cardiovascular disease procedures31990–2007NocYesNo
  Diabetic amputations31990–2007NocNoNo
  Diabetic eye complications32006–2007NocNoNo
 ANZDATAfDialysis treatment prevalenceg31997–2006YesNoNo

Maternal/ newborn indicators

Figure 1 shows the trends in five indicators by Aboriginal status and area of residence. During the period 1994–2007, the prevalence of pre-term (less than 37 weeks of gestation) and low birth-weight (less than 2500 gram) babies born to Aboriginal mothers remained significantly higher than for babies born to non-Aboriginal mothers in all areas (p<0.001). Smoking prevalence in pregnancy declined for all mothers, but remained much higher for Aboriginal mothers (p<0.001). A higher, stable rate of teenage pregnancies was observed among Aboriginal mothers (p<0.001). There have been improvements in access to timely antenatal care for all mothers and, although a significant difference remains (p<0.001), there has been a narrowing of the gap between Aboriginal and non-Aboriginal mothers. The proportion of NSW Aboriginal mothers starting antenatal care before 20 weeks gestation has risen from 63.0% in 1994 to 79.5% in 2007, with a notable improvement in major cities.

Figure 1.

Maternal and newborn health indicators by Aboriginal status and region in NSW, 1994–2007.

Data Source: The NSW Midwives data collection (MDC), 1994–2007 (HOIST) Centre for Epidemiology and Research, NSW Department of Health.

Figure 2 shows the age-adjusted hospitalisation rates for the period 1993/94 to 2006/07 for diabetes and CVD-related conditions for the NSW population, by Aboriginal status and the age-adjusted rates of dialysis treatments for the Aboriginal and total NSW population. These data reflect the increased disease burden experienced by Aboriginal people for these three conditions. While hospitalisations of non-Aboriginal people for CVD have declined by 11% over this period, the rate among Aboriginal people has increased by 25%. By contrast, the diabetes hospitalisation rate has risen for all people, with Aboriginal people experiencing a 3.1 times greater rate of hospitalisations than non-Aboriginal people in 2006/07 (p<0.001). Similarly, while the rates of dialysis treatments have risen for both the Aboriginal and total NSW population, Aboriginal people experienced a 1.8 times greater rate of dialysis treatments than experienced by the total NSW population in 2007 (p<0.001).

Figure 2.

Diabetes and Cardiovascular disease hospitalisations rates, Dialysis treatment rates by Aboriginal status and sex in NSW, 1993/94 to 2006/07.

Figure notes

1) Data Sources: NSW Admitted Patient Data Collection 1993–94 to 2006–07 (HOIST), Centre for Epidemiology and Research, NSW Department of Health, Australian and New Zealand Dialysis and Transplant Registry.

2) Data for all three graphs were age adjusted using the estimated resident population for NSW 1993–2006 as the reference population and the Australian population as at 30 June 2001 as the standard.

3) Dialysis treatment prevalence refers to the population prevalence of maintenance dialysis provided for end-stage kidney disease (both peritoneal and haemodialysis). It includes hospital, satellite and community-based (home) dialysis.

Vascular disease indicators

Table 3 shows the estimated prevalence of selected vascular risk factors for Aboriginal people and for the total NSW population over a similar time period. Owing to the small sample size for Aboriginal people in the PHS (n=930), the wide 95% confidence intervals around these estimates results in large imprecision. Nevertheless, when compared with the total population surveyed in 2005, Aboriginal males have approximately double (p<0.01) and Aboriginal females approximately three times (p<0.001) the rate of self-reported current smoking. A significantly higher prevalence of overweight and obesity for urban-residing Aboriginal females (approximately 1.4 times greater, p<0.05) was also noted.

Table 3.  Vascular risk factor prevalence rates for persons aged 16 years and over by Aboriginal status and sex in NSW.
Risk factorPopulationUrbanRural
  Males % (95% CI)Females % (95% CI)Males % (95% CI)Females % (95% CI)
  1. Data Sources: 2002–2005 Report on Adult Aboriginal Health and the 2005 Report on Adult Health from the New South Wales Population Health Survey (PHS).20,21

Current daily or occasional smokingAboriginal 2002–200541.3 (28.3–54.3)41.1 (32.1–50.2)46.7 (38.2–55.2)42.2 (35.3–49.0)
 Total NSW 200521.6 (19.4–23.8)16.6 (15.0–18.2)25.1 (22.7–27.6)19.9 (18.2–21.6)
Diabetes or high blood glucose (as notified by a doctor or hospital-excludes gestational diabetes)Aboriginal 2002–20055.1 (0.8–9.5)5.8 (2.0–9.5)15.3 (9.9–20.8)12.4 (8.0–16.8)
 Total NSW 20058.3 (7.0–9.5)6.8 (5.8–7.7)8.6 (7.4–9.8)7.0 (6.0–8.0)
Overweight and obesity (Body mass index >25 kg/m2)Aboriginal 2002–200548.9 (35.5–62.3)53.2 (43.6–62.8)62.1 (53.3–70.8)53.3 (46.0–60.6)
 Total NSW 200555.5 (52.9–58.1)39.3 (37.2–41.4)62.0 (59.4–64.6)49.2 (47.1–51.3)
Adequate fruit consumption (at least two serves per day)Aboriginal 2002–200532.0 (19.8–44.2)41.7 (32.9–50.6)34.5 (26.5–42.5)39.9 (33.3–46.4)
 Total NSW 200544.4 (41.9–47.0)57.6 (55.5–59.7)44.9 (42.2–47.5)57.4 (55.3–59.5)
Adequate vegetable consumption (at least five serves per day)Aboriginal 2002–20057.6 (2.0–13.2)17.0 (9.6–24.3)4.1 (1.8–6.5)13.0 (8.4–17.7)
 Total NSW 20054.0 (3.0–4.9)8.9 (7.8–10.0)6.4 (5.2–7.6)12.7 (11.5–14.0)
Adequate physical activity (at least 150mins per week on five separate occasions)Aboriginal 2002–200568.7 (56.6–80.9)44.0 (34.9–53.2)51.8 (43.3–60.3)46.7 (39.9–53.6)
 Total NSW 200557.1 (54.4–59.7)48.2 (46.0–50.3)55.4 (52.8–58.0)45.5 (43.4–47.6)

Box 1: Description of the three NSW data collections examined.

The Midwives Data Collection (MDC)

The MDC is a population-based surveillance system covering births of at least 20 weeks gestation or 400 grams birth weight in public and private hospitals, including home births. Data are collected on maternal socio-demographic characteristics, reproductive history, pregnancy and perinatal outcomes. A validation study found that the majority of MDC data items have more than 90% inter-rater agreement and kappa coefficients above 0.70.43 Data on maternal Aboriginal status, but not the Aboriginal status of the baby, are routinely collected. MDC data are linked to birth registration records from the Registry of Births, Deaths and Marriages to assess enumeration of maternal Aboriginal status, In NSW this enumeration rate was estimated to be 69.3% in 2005.23

The Population Health Survey (PHS)

The PHS is an annual computer-assisted telephone survey which commenced in 2002. It collects information about health behaviours, health status, health service use and access, and social capital. A stratified two-stage cluster sample design is used by targeting a sample of 1500 people in each AHS per year. Weighting factors are used to estimate the rates at AHS and state level. Eight hundred Aboriginal participants are estimated to be needed to detect a 5% difference in prevalence estimates.20 Between 2002 and 2005, 56,677 adult respondents (aged 16+) participated in the survey; 930 were Aboriginal. When compared with the 2001 census figures, Aboriginal survey respondents were more likely to be female (61.3%) and to reside in a rural area (65.6%).20 One report on Aboriginal adult health has been published based on these data20 with the next report expected in 2010.

The Admitted Patient Data Collection (APDC)

The APDC provides data each financial year, covering services provided by public hospitals (including psychiatric), public multi-purpose services, private hospitals and private day procedure centres for admitted patients. It includes data on interstate hospital admissions of NSW residents.11 From 1998, the APDC changed from reporting admissions to reporting episodes of care. This might have lead to a small increase in enumeration. A validation study found that enumeration of Aboriginal status in the APDC was 88% overall – 81% in urban, 89% in inner regional, 95% in outer regional and 100% in remote areas.11

Discussion

This review of indicators routinely reported by NSW Health has assessed how adequately those measures report outcomes by Aboriginal status against national indicators in two priority areas – maternal/newborn health and vascular diseases. The major obstacles to improved monitoring relate to both the quality and breadth of indicators currently reported. NSW Health reports on a range of chronic disease-related indicators in other areas (e.g. psychosocial, respiratory and environmental health) and augments this reporting with ad hoc research and information from national data collections. We do not make any assumptions about the quality of reporting by Aboriginal status in these other areas. For the indicators examined here, the most persistent problem affecting data quality is enumeration of Aboriginal status. For the APDC, the estimated enumeration rate of 88% is reasonable and does not, therefore, preclude useful data interpretation. The MDC, however, has persistently low enumeration rates of around 70%. Data linkage using administrative datasets is a promising area, both for quantifying and improving enumeration. Using data linkage, the 2006/07 ABS Census Data Enhancement – Indigenous Mortality Quality Study estimated NSW enumeration of Indigenous status to be 87%– substantially better than previously reported.25 NSW Health has been conducting data linkage research to enhance MDC enumeration. It is expected that revised enumeration estimates will be used in future reports.

We found other important limitations in data quality and breadth. The key additional problem with both NSW and national perinatal statistics collections is that they report by Aboriginal status of the mother and not of the baby. In NSW and nationally, 36% and 28%, respectively, of registered Aboriginal births have an Aboriginal father and non-Aboriginal mother.26 This leads to gaps in our understanding of health outcomes for a large proportion of Aboriginal babies. The OATSIH Healthy for Life program and a Northern Territory indicator program are now reporting data by Aboriginal status of the baby.16,27 The next NSW Health Mothers and Babies report is expected to follow suit.

For the APDC data, only two indicators (CVD and diabetes hospitalisations) are routinely reported by Aboriginal status. Although known areas of disparity, access to CVD-related procedures and rates of diabetes complications are not regularly reported by Aboriginal status or region.28,29 Only one CKD-related indicator, dialysis treatment prevalence, was identified.Figure 2 demonstrates an apparent divergence between the rapid increase in diabetes hospitalisation rates and levelling out of dialysis prevalence, especially among Aboriginal women. This could be explained by delays between the onset of diabetes and the manifestation of end-stage kidney disease (ESKD), or by competing mortality from premature CVD, or by poor dialysis outcomes, which might reduce the increase in dialysis prevalence despite rising incidence of ESKD. Because of marked regional variation in ESKD incidence,30 evidence of poorer access to dialysis in rural and remote areas,31 and high rates of CKD risk factors in primary healthcare,32 more comprehensive monitoring with a broader range of indicators is warranted.

A limitation to the PHS data relates to sampling. Because the 2002–05 report on adult Aboriginal health did not have an a priori design, a convenience sample was gathered over three years to obtain an adequately powered sample size. There is an over-representation of females and rural respondents. Conversely, telephone-assisted data collection might lead to a substantial under-representation of Aboriginal people in remote areas, given that only 43% of Aboriginal households in remote areas and 82% in non-remote areas report having a working telephone.33 NSW Health currently uses ‘Bayesian smoothing techniques’ to get better estimates at small geographical levels for the total population. This method has not been tested for Aboriginal populations, however, and its limitations are not yet known. It is also likely that assessing the prevalence of health conditions based on self-report surveys produces under-estimates.34 Combining health surveys with physical and laboratory measures, as is done in the US National Health and Nutrition Examination Survey,35 would allow for more comprehensive estimates of health status. Linking data from such surveys to primary care, hospitalisations and mortality data would allow for measurement at multiple points in the system. The NSW ‘45 and up’ population-based cohort study of 260,000 people plans to link self-reported survey data with other datasets; specific sub-studies will include physical/ laboratory measures.36 Although restricted to those aged 45 and over, 0.8% of the sample (2,149 people) identify as Aboriginal and/or Torres Strait Islander. This, one of the largest cohorts ever assembled, should facilitate an understanding of health status, resource utilisation and outcomes for this population.

Another objective of this review was to assess preparedness to monitor progress in the proposed national health reforms. When classified using the HPF, most of the indicators regularly reported by Aboriginal status come from Tier 1 (health status) and Tier 2 (health behaviours). Many of the current Tier 3 (health system performance) indicators are derived from the primary healthcare sector and are traditionally considered a federal responsibility. Increased coordination between primary, secondary and acute care services, as highlighted in the NSW State Health Plan37 and in the proposed health reforms,2,4,5 are needed to enhance performance monitoring. The ‘Close the Gap’ Steering Committee recommends several new primary-care based Tier 3 health indicators which expand considerably on the current diabetes-focused indicators.18 Current primary care data monitoring is poorly equipped to monitor such indicators. Accurate enumeration of Aboriginal and Torres Strait Islander status, universal uptake of electronic medical record systems, consistent and reliable data entry, electronic management and auditing tools and regular reporting mechanisms are needed to effectively monitor primary care. Recent initiatives in the Aboriginal Community Controlled Health Services (ACCHS) sector16,27,38 hold promise, but mechanisms in the non-ACCHS primary care sector are considerably under-developed. The new reporting requirements for the Divisions of General Practice17 and initiatives such as the Australian Primary Care Collaboratives39 are potential avenues for addressing this problem.

The problems of insufficient breadth and quality of indicators are not restricted to New South Wales. Extensive reviews of health system monitoring for Indigenous peoples in Canada40 and New Zealand41 highlight that the issues identified in this paper are pertinent to all three countries. It is essential, therefore that there be an appropriate, minimum chronic disease indicator dataset again, which all jurisdictions can report by Aboriginal status and region. The Aboriginal and Torres Strait Islander HPF, the most advanced national indicator framework, is a suitable reference point for developing this dataset. Several inter-related factors ought to be considered in developing such a dataset. First, although the focus of this study was vascular and maternal/infant health, there is a need to include health systems process indicators, which are not condition specific. Attention to such indicators, ideally linked to health outcomes, can facilitate an early ‘diagnosis’ of health systems problems and can anticipate reasons for delays in progress on health status improvements. Second, any proposed indicator needs to be of sufficient quality to warrant inclusion. The AIHW chronic disease indicator project group considered a quality indicator to be one that was relevant, applicable across population groups, technically sound (valid, reliable, sensitive to change, robust) and feasible to collect. It also needed to be timely, marketable and lead to action.42 Third, Indigenous academics and representative bodies have long argued for full participation in determining how health system performance is measured. This includes the need to embrace Indigenous concepts of health into systems measurement, building local monitoring systems at the community level to complement macro-system monitoring, and making data feedback more accessible to the communities and health services whence these data originate.7 The NT and Queensland indicator programs,27,38 developed by the ACCHS sector, are two successful models that adhere to these principles.

With the proposed national health reforms gaining momentum and substantial funding becoming available for COAG ‘Close the Gap’ initiatives, there is renewed vigour in addressing Aboriginal and Torres Strait Islander health disparities. Despite the challenges in ensuring robust data, it is imperative that health systems are not paralysed by waiting for perfect data before taking action. The persistent and wide disparities in health outcomes, in relation to the indicators reported in this paper, substantially outweigh data quality concerns. Nevertheless, reliable measurement of progress in addressing these disparities is needed. This requires population-representative data from the primary healthcare sector, improved coordination between hospitals and primary care, improved health survey sampling with the incorporation of physical/laboratory measures and sustained efforts to address under-enumeration (especially data-linkage initiatives). The NSW CHO Report and the Chartbook on the quality and safety of healthcare in NSW are useful tools for facilitating healthcare improvements. Through future Chartbook iterations, the CEC will monitor progress on health disparities across individuals’ life-courses and engage with key stakeholders to improve health outcomes for Aboriginal and Torres Strait Islander people.

Acknowledgements

We gratefully acknowledge Helen Moore and Margo Barr from the Centre for Epidemiology and Research, NSW Department of Health, for critically reviewing an earlier version of the manuscript. We also thank Peter Arnold for his help in editing this paper. Florence Sofield provided helpful comments on Table 1 and valuable information about the Healthy for Life indicators. David Peiris is supported by the NSW Clinical Excellence Commission Ian O'Rourke scholarship for patient safety. Alan Cass is a recipient of a NHMRC Senior Research Fellowship.

Ancillary