Australian Government: Australian Institute of Health and Welfare METeOR Home Page

National Disability Agreement: (c)-Proportion of the potential population accessing disability services, 2012 QS

Identifying and definitional attributes

Metadata item type:Help on this termQuality Statement
METeOR identifier:Help on this term478373
Registration status:Help on this termCommunity Services (retired), Standard 05/03/2012

Relational attributes

Indicators linked to this Quality statement:Help on this term

National Disability Agreement: c(1)-Proportion of the potential population accessing disability services, 2012 Community Services (retired), Superseded 23/05/2013

National Disability Agreement: c(2)-Proportion of the potential population accessing disability services, 2012 Community Services (retired), Superseded 23/05/2013

Data quality

Quality statement summary:Help on this term

1. DS/CSTDA NMDS data are generated by processes that deliver services to people. It is assumed that these processes involve the determination of eligibility and the assessment of  disability support needs following broadly consistent principles across jurisdictions, although it is known that differing assessment tools are in use across jurisdictions. This assumption is untested.

2. Data measuring the potential population is not explicitly available for the required time point and so has been estimated from several difference sources under several key assumptions. The assumption of constant age-sex specific rates of severe/profound core activity limitation over time is contradicted by comparison of age-sex specific rates of severe/profound core activity limitation from SDAC 2003 and SDAC 2009, which indicate an overall slight decline in rates between these two time periods. A further assumption that national level age-sex specific rates of severe/profound core activity limitation from the 2009 SDAC apply consistently across states/territories is untested.

3. There are issues with the consistency of the numerator and denominator for this performance indicator, as the numerator and denominator are drawn from differently defined populations and different data sources.

Institutional environment:Help on this term

The AIHW is an Australian Government statutory authority accountable to Parliament and operates under the provisions of the Australian Institute of Health and Welfare Act 1987. The AIHW provides expert analysis of data on health, housing and community services. More information about the AIHW is available on the AIHW website.

For general issues relating to the DS/CSTDA NMDS, refer to the DS/CSTDA NMDS Data Quality Statement.

For information on the institutional environment of the ABS, including the legislative obligations of the ABS, please see ABS Institutional Environment.

Timeliness:Help on this term

CSTDA NMDS 2008–09 and DS NMDS 2009–10.

ABS SDAC 2009; Census 2006; Estimated Resident Population at 30 June 2008 and 30 June 2009.

Accessibility:Help on this term

The AIHW provides a variety of products that draw upon the DS/CSTDA NMDS. Published products available on the AIHW website are:

  • Disability support services (annual report)
  • Australia’s Welfare
  • Interactive disability data cubes
  • Ad hoc data are available on request (charges apply to recover costs)
  • METeOR – online metadata repository
  • National Community Services Data Dictionary.

The ABS website provides information and data on the ERP, Census Need for Assistance and SDAC profound/ severe core-activity limitation. Detailed data extractions are available through the National Information Referral Service (cost-recovery applies).

Interpretability:Help on this term

Information to assist in interpretation of the performance indicator is contained in the NDA performance indicator glossary, which accompanies these Data Quality Statements.

Supporting information on the quality and use of the DS/CSTDA NMDS are published annually in ‘Disability support services’ available in hard copy or on the AIHW website (<www.aihw.gov.au>).

Relevance:Help on this term

Data from several different sources, each referencing different time periods, are used to produce performance indicator (c). Data used are from the CSTDA NMDS 2008–09 and DS NMDS 2009–10, SDAC 2009, ERP June 2008 and June 2009, and Census 2006. This may reduce the overall accuracy of the estimates. In particular,

  • Data from the CSTDA NMDS 2008–09 and DS NMDS 2009–10, ERP June 2008 and June 2009 and Census 2006 cover all geographical areas of Australia, whereas the SDAC 2009 does not cover very remote areas nor Indigenous communities.
  • The use of SDAC 2009 age-sex specific rates of severe/profound core activity limitation to calculate 2008 and 2009 estimates of potential population assumes these rates to be consistent over time.  A comparison of age-sex specific rates of severe/profound core activity limitation from SDAC 2003 and SDAC 2009 indicates that most age-sex specific rates have declined between these two time periods.  Overall, the rate of severe/profound core activity limitation for people aged 0-64 years has declined from 3.9% in 2003 to 3.6% in 2009.
  • The use of national level SDAC 2009 age-sex specific rates of severe/profound core activity limitation assumes these rates to be consistent across states/territories. This assumption is untested.
  • Information from Census 2006 about people with need for assistance with core activities is based on the self enumerated completion of four questions, whereas people are defined as having a severe/profound core activity limitation in SDAC 2009 on the basis of a comprehensive interviewer administered module of questions, and thus the two populations are different although they are conceptually related.
  • The use of Census 2006 data about country of birth and Remoteness Area distributions for people with need for assistance with core activities assumes these distributions to be consistent over time. This assumption is untested.

DS/CSTDA NMDS data are generated by processes that deliver services to people. It is assumed that these processes involve the determination of eligibility and the assessment of disability support needs following broadly consistent principles across jurisdictions, although it is known that differing assessment tools are in use across jurisdictions. This assumption is untested.

The scope of services provided under the CSTDA/NDA varied across jurisdictions. In Victoria, Queensland and Western Australia (in some cases), specialist psychiatric disability services were provided under the CSTDA/NDA.  In all other jurisdictions specific mental health services were funded and provided under health, rather than disability, portfolios.  To facilitate comparability of data, specialist psychiatric disability services in Victoria, Queensland and Western Australia are excluded from the NDA performance indicators.  That is, the data excludes those who only receive specialist psychiatric disability services, but does not exclude those people with a psychiatric condition who receive other specialist disability services. In addition, the predominant service models vary across jurisdictions, and this may affect comparability of data. For example, differences across the states and territories in the predominant model of accommodation support lead to differences in the number of people accessing those services. Caution is recommended in the use or interpretation of performance at the service type level. There is a risk when service type level data is interpreted in isolation as various service types are complementary and the emphasis on different services reflects jurisdictional policy directions. For more information, see Disability support services 2008–09 and Disability support services 2009–10 (forthcoming).

Accuracy:Help on this term

Potential sources of error in the DS/CSTDA NMDS are data items for which the response is not stated or not collected. If the characteristics of the people for whom the information is not available are different to those people for whom information is reported, there is potential for bias to be introduced into the data. Not stated/not collected rates vary substantially across jurisdictions and data items. The data item need for assistance has a particularly high not stated/not collected rate. For the 2009–10 data set the rate was 13.1% overall, ranging from 0.0% for Australian Government agencies to 42.2% for Victoria. For the 2008–09 data set the rate was 14.1% overall, ranging from 0.2% for Australian Government agencies to 41.8% for Victorian agencies.

For general issues relating to the DS/CSTDA NMDS, refer to the DS/CSTDA NMDS Data Quality Statement.

Being a sample survey, estimates from the SDAC 2009 are subject to sampling variability. A measure of the sampling variability, the relative standard error (RSE) percent, is estimated below for the age-sex specific rates of severe/profound core activity limitation.

Estimated RSE for age-sex rates of severe/profound core activity limitation at national level (percent)

Age group (years) Male Female
0-4
5-14
15-24
25-34
35-44
45-54
55-59
60-64
13.2
6.5
11.6
11.9
9.3
8.1
9.7
7.9
18.3
10.2
13.7
9.5
9.3
8.4
7.1
7.8

Source: Disability, Ageing and Carers, Australia: Summary of Findings, 2009. ABS cat. no.4430.0.

Potential sources of error in Census data include failure to return a Census form or failure to answer applicable questions. Data distributions calculated from Census 2006 data excluded people for whom data item information was not available. Should the characteristics of interest of the people excluded differ from those people included, there is potential for bias to be introduced into the data distributions. Quality statements about Census 2006 data items can be found on the ABS website.

Coherence:Help on this term

For general issues relating to the DS/CSTDA NMDS refer to the DS/CSTDA NMDS Data Quality Statement.

There are issues with the consistency of the numerator and denominator for this performance indicator, as the numerator and denominator are drawn from differently defined populations and different data sources. These issues reduce the consistency of the performance indicators and lead to quality issues such as cells greater than 100%.

While the numerator is taken from the DS/CSTDA NMDS, the denominator is an estimate derived from SDAC, ERP and Census data. In the denominator, ‘estimated potential population for specialist disability services’ is defined as the estimated population with severe or profound core activity limitation. However, this does not match well with the numerator, which consists of people who used specialist disability services. People who used these services do not necessarily have a severe or profound core activity limitation (mobility, communication, or self-care). They may instead have a mild/moderate core activity limitation or limitations in other activities—for example, with working or education. This mismatch is more evident in certain types of services, such as open employment services, which are not necessarily tailored towards people with a severe or profound core activity limitation.

For the calculation of potential population for the denominator, the method used to calculate the country of birth and remoteness disaggregation’s is the same as that adopted by the Disability Services Working Group for calculation of special needs group indicators in the Report on Government Services 2011.

Relational attributes

Related metadata references:Help on this term

Supersedes National Disability Agreement: c(1)-Proportion of the potential population accessing disability services, 2011 QS Community Services (retired), Superseded 05/03/2012

My items Help on this term
Download Help on this term