Identifying and definitional attributes
|Metadata item type:||Quality Statement|
|Registration status:||Health, Superseded 14/01/2015|
|Indicators linked to this Quality statement:|
National Healthcare Agreement: PI 03-Prevalence of overweight and obesity, 2013 Health, Superseded 30/04/2014
The Australian Health Survey (AHS) was collected, processed, and published by the Australian Bureau of Statistics (ABS). The ABS operates within a framework of the Census and Statistics Act 1905 and the Australian Bureau of Statistics Act 1975. These ensure the independence and impartiality from political influence of the ABS, and the confidentiality of respondents.For more information on the institutional environment of the ABS, including the legislative obligations of the ABS, financing and governance arrangements, and mechanisms for scrutiny of ABS operations, please see ABS Institutional Environment.
The AHS is conducted every three years over a 12 month period. Results from the 2011-12 National Health Survey (NHS) component of the AHS were released in October 2012.
|Accessibility:||See Australian Health Survey: First Results (cat. no. 4364.0.55.001) for an overview of results from the NHS component of the AHS. Other information from this survey is also available on request.|
Information to aid interpretation of the data is available from the Australian Health Survey: Users’ Guide (cat. no. 4363.0.55.001) on the ABS website.
Many health-related issues are closely associated with age; therefore data for this indicator have been age-standardised to the 2001 total Australian population to account for differences in the age structures of the States and Territories. Age standardised rates should be used to assess the relative differences between groups, not to infer the rates that actually exist in the population.
The 2011-13 Australian Health Survey collected measured height and weight from persons aged 2 years and over. For the purposes of this indicator, Body Mass Index (BMI) values are derived from measured height and weight information using the formula: weight (kg) / height (m)2.Despite some limitations, BMI is widely used internationally as a relatively straightforward way of measuring overweight and obesity.
The AHS is conducted in all States and Territories, excluding very remote areas. Non-private dwellings such as hotels, motels, hospitals, nursing homes and short-stay caravan parks were also not included in the survey.
The exclusion of persons usually residing in very remote areas has a small impact on estimates, except for the Northern Territory, where such persons make up a relatively large proportion of the population. The response rate for the 2011-12 NHS component was 85 per cent. Results are weighted to account for non-response.
As it is drawn from a sample survey, the indicator is subject to sampling error. Sampling error occurs because only a small proportion of the population is used to produce estimates that represent the whole population. Sampling error can be reliably estimated as it is calculated based on the scientific methods used to design surveys. Rates should be considered with reference to their Relative Standard Error (RSE).
Estimates with RSEs between 25 per cent and 50 per cent should be used with caution. Estimates with RSEs greater than 50 per cent are generally considered too unreliable for general use.
Data for Northern Territory in 2011-12 is not comparable to previous years due to the increase in sample size.
RSEs for adult overweight and obesity rates by State/Territory and Remoteness Areas are generally within acceptable limits, except for remote areas in New South Wales and Tasmania where rates are considered too unreliable for general use.
The breakdown by State/Territory and SEIFA quintiles for adults in general has sampling error within acceptable limits. For children, remoteness and SEIFA disaggregations by State/Territory should generally be used with caution.
Adult overweight and obesity rates by age and sex generally have acceptable levels of sampling error at the State/Territory level, though some of the rates for females in Australian Capital Territory and Northern Territory should be used with caution.
Sampling errors for BMI data for adults by State/Territory are generally within acceptable limits, though rates of underweight for most States/Territories should be used with caution. The underweight rates for children in New South Wales, Tasmania, Australian Capital Territory and Northern Territory should be used with caution.
Rates of overweight and obesity for adults by State/Territory and disability status are within acceptable limits. For children with disability, rates of overweight and obesity should generally be used with caution.The accuracy of overweight and obesity rates, particularly at the finer disaggregation levels is expected to improve in the 2014 reporting cycle with the use of the core sample of 34,000 people. For information on AHS survey design, see the Australian Health Survey: Users’ Guide (cat. no. 4363.0.55.001) on the ABS website.
The methods used to construct the indicator are consistent and comparable with other collections and with international practise.
Most surveys, including CATI health surveys conducted by the States and Territories, collect only self-reported height and weight. There is a general tendency across the population for people to overestimate height and underestimate weight, which results in BMI scores based on self-reported height and weight to be lower than BMI scores based on measured height and weight.
The age- and sex-specific cutoff points for BMI categories for children are from the work of Cole TJ, Bellizzi MC, Flegal KM & Dietz WH 2000, “Establishing a standard definition for child overweight and obesity worldwide: international survey”, BMJ 320:1240.The AHS collected a range of other health-related information that can be analysed in conjunction with BMI.
Source and reference attributes
|Submitting organisation:||Australian Bureau of Statistics|
|Related metadata references:|
Supersedes National Healthcare Agreement: P05-Proportion of persons obese, 2010 QS Health, Superseded 12/03/2015
Has been superseded by National Healthcare Agreement: PI 03-Prevalence of overweight and obesity, 2014 QS Health, Superseded 14/01/2015