National Aboriginal and Torres Strait Islander Health Survey methodology

The 2022–23 National Aboriginal and Torres Strait Islander Health Survey (NATSIHS) is a component of the wider Intergenerational Health and Mental Health Study (IHMHS) funded by the Australian Government Department of Health and Aged Care.

The 2022–23 NATSIHS was conducted from August 2022 to March 2024. Data was collected from approximately 4,900 households around Australia, in both non-remote and remote areas, including discrete Indigenous communities.

The survey focused on the health of Aboriginal and Torres Strait Islander people. Information was collected about respondents' long-term health conditions and on risk factors which may affect health, such as tobacco smoking and vaping, alcohol consumption, fruit and vegetable consumption, and physical activity. Self-reported health status, height, and weight were also collected. Respondents could voluntarily provide blood pressure, height, weight and waist measurements.

Some topics were included for the first time in the 2022–23 NATSIHS, including questions about food security, personal use of the internet, unpaid care, cultural safety, and the use of health services for mental health. The survey included questions about stressors and barriers to service providers which were last included in the 2014–15 National Aboriginal and Torres Strait Islander Social Survey (NATSISS). 

The survey also collected a standard set of information about respondents including age, sex, main language, employment, education, and income.

The 2022–23 NATSIHS is considered to be comparable with the 2018–19 NATSIHS and previous cycles. Previous surveys were conducted in 2012–13 and 2004–05. The 2001 National Health Survey also included an Aboriginal and Torres Strait Islander sample. Some health data was also collected in the 2014–15, 2008 and 2002 NATSISS. Differences from the 2018–19 NATSIHS are detailed in the Data Item List in the Data downloads section. For more information, see the Comparability with previous surveys section. 

The survey was possible thanks to the high level of cooperation from our Aboriginal and Torres Strait Islander peoples and their communities. Without their continued support of our ABS surveys, the collection of data and the wide range of information available for Aboriginal and Torres Strait Islander peoples published by the ABS would not be possible.

The survey was developed following extensive consultation to identify priority data requirements and data gaps. In addition to consulting with key stakeholders from government, research and community organisations, workshops were held with Aboriginal and Torres Strait Islander community members to capture their thoughts about issues that are critical to Aboriginal and Torres Strait Islander people, their families and communities.

• Advisory and reference groups were established to assist the ABS in determining the content of the survey and to advise on data output requirements.
• Expert advisory panels provided advice to the ABS on selected topics. These panels comprised members from both government and non-government agencies.
• New questions proposed for inclusion underwent cognitive testing to ensure concepts would be understood by respondents, and to enable the questions and associated procedures to be refined.

A dress rehearsal was conducted in late 2021 to test survey content and procedures. The sample was limited due to external factors including the COVID-19 pandemic.

The range of topics identified for possible inclusion exceeded the capacity of the survey. With the assistance of the advisory and reference groups, topics were prioritised then shortlisted. Topics ultimately selected for inclusion in the survey were those identified as highest priority which could be appropriately collected in a survey of this type. 

The scope of the survey was all Aboriginal and Torres Strait Islander people living in private dwellings.

The following people were not included in the survey:

• non-Indigenous persons
• visitors to private dwellings staying for less than 6 months
• people in households where all usual residents were less than 18 years of age
• people who usually lived in non-private dwellings, such as hotels, motels, hostels, hospitals, nursing homes and short-stay caravan parks
• students at boarding school
• non-Australian diplomats, diplomatic staff and members of their household
• members of non-Australian defence forces stationed in Australia and their dependents
• overseas visitors.

Coverage exclusions apply to those people who were in scope for the survey, but who were not included in the sampling frame. The following coverage exclusions were applied:

• mesh blocks with no or very few Aboriginal and Torres Strait Islander households
• some discrete Indigenous communities and outstations with a small number of Aboriginal and Torres Strait Islander households
• long-stay caravan parks and marinas.

The overall coverage of the 2022–23 NATSIHS was approximately 25% of Aboriginal and Torres Strait Islander persons in Australia. The final sample has been weighted to population benchmarks which align with the scope of the survey to account for undercoverage. For more information, see the How the data is processed section.

The survey was designed to produce reliable estimates for the whole of Australia, for each state and territory and for remoteness areas. The sample was designed to achieve a Relative Standard Error of less than 25% for key variables.

The survey sample had 2 parts:

• a community sample, made up of discrete Indigenous communities, including any outstations associated with them, and
• a non-community sample, made up of private dwellings within areas outside of Indigenous communities.

Each part used a multi-stage sampling process to ensure the representativeness of the final sample.

As with previous ABS Aboriginal and Torres Strait Islander surveys, additional sample was collected in the Torres Strait Area, to ensure data of sufficient quality would be available for the Torres Strait Area and the remainder of Queensland.

The community sample was a random selection of discrete Indigenous communities and outstations in non-remote and remote areas.

• Selections were made using the Dwelling Register for Aboriginal and Torres Strait Islander Communities (DRATSIC). The DRATSIC was constructed from counts from the 2016 Census of Population and Housing.
• Communities in Tasmania were excluded from coverage entirely, consistent with the 2018–19 NATSIHS.
• Communities in Victoria were excluded from coverage entirely, after feedback from the 2021 Census that there were no community addresses found.
• Non-remote communities in Western Australia and the Northern Territory were excluded from coverage as only a small number of fully responding households were required in the sample design. As a result, these communities were removed from the sample, which was consistent with the 2018–19 NATSIHS.

Dwellings in the non-community sample were selected using a stratified multi-stage area sample.

• Mesh blocks with no Aboriginal and Torres Strait Islander households, as identified in the 2021 Census, were excluded from coverage.
• Areas in remote Victoria and very remote Tasmania were excluded, consistent with the 2018–19 NATSIHS.
• For each randomly selected dwelling within the selected mesh block, one usual resident aged 18 years or over was asked whether anyone in the household was of Aboriginal and/or Torres Strait Islander origin. This screening question was used to identify Aboriginal and Torres Strait Islander households, from which the sampling process was undertaken for participants in the survey.

Within each identified Aboriginal and Torres Strait Islander household in both the community and non-community sample:

• up to two adults (aged 18 years and over) and two children (aged 0–17 years) were randomly selected in non-remote areas, and
• up to one adult (aged 18 years and over) and one child (aged 0–17 years) were randomly selected in remote areas.

The sample design had an expected number of 11,662 fully responding persons. The final survey data file had 7,768 fully responding persons, the calculation of which is explained below.

A total of 8,488 households were selected in the sample. These were identified by screening households in non-community areas and through selections of discrete Indigenous communities. The sample was then reduced to 7,839 households after excluding those unable to be contacted after screening.

Of the 7,839 households in the final sample, 4,878 (62.2%) were fully or adequately responding households. These are households where at least one person selected to complete the survey had either completed it fully or to a point where their data could still be used.

From the 4,878 fully or adequately responding households, there were 7,768 people included in the final sample.

In the ACT, the number of Aboriginal and Torres Strait Islander households identified during the screening process was lower than expected, compared to initial sample design assumptions. As a result, the number of fully responding households in the final sample is not large enough to support estimates of suitable quality for the ACT being published separately. These households are included in national estimates.

Interviewer training

Information was collected by trained ABS interviewers using a computer-based questionnaire. Prior to enumeration, interviewers:

• participated in cultural awareness training which described cultural considerations and sensitivities around conducting surveys with the Aboriginal and Torres Strait Islander population
• completed classroom training and exercises to gain an understanding of the survey content and procedures.

Face-to-face interviews

Interviewers conducted face-to-face interviews in all selected households.

A person aged 18 years or over was asked to provide basic information for all usual residents of the household, including Indigenous status, age, sex and relationships. A usual resident of the household aged 18 years or over, known as the household spokesperson, then answered financial and housing questions, such as income, tenure arrangements, household facilities and food security.

Personal interviews were then conducted with selected Aboriginal and Torres Strait Islander persons aged 15 years and over. Some people were unable to be interviewed because:

• of injury or illness (a proxy interview may have been arranged)
• of cultural considerations, such as mourning the death of a family member (sorry business) or
• an interpreter was required and unable to be arranged.

For selected persons aged 15–17 years:

• a personal interview was conducted if a parent or guardian provided consent, or
• their interview was completed by a proxy (that is, by a parent or guardian). Around two-thirds (65%) of interviews were conducted by proxy for this age group, which is a similar rate to that recorded in the 2018–19 NATSIHS.

A parent or guardian was required to be present for any personal interviews conducted with persons aged 15–17 years.

An adult was asked to respond on behalf of children aged less than 15 years.

Use of local Aboriginal and Torres Strait Islander advisors

In communities and in some regional areas, interviewers were accompanied, where possible, by local Aboriginal and Torres Strait Islander advisors who assisted in conducting interviews. The advisors:

• explained the purpose of the survey
• introduced the interviewers, and
• assisted in identifying usual residents of a household and in locating residents who were not at home.

Variations in data collection and survey questions in remote areas

To take account of language and cultural differences, the collection method and survey questions sometimes varied in remote areas.

• Some questions were reworded to enhance a person’s ability to understand concepts.
• Some topics were excluded if it was considered problematic to collect or not applicable.

This means some data items are not available for the total Aboriginal and Torres Strait Islander population. For more information on the availability of data items, see the Data Item List in the Data downloads section.

The survey collected the following content:

• demographics – age, sex, language, social marital status
• household details – type, size, household composition, tenure, Socio-Economic Indexes for Areas (SEIFA), geography
• food security and financial stress
• cultural identification
• labour force status
• educational attainment
• personal and household income
• personal use of the internet
• self-assessed health status 
• self-reported height and weight
• long-term health conditions such as arthritis, asthma, cancer, diabetes, hypertension, kidney disease, mental and behavioural conditions
• health risk factors such as smoking, alcohol consumption, fruit and vegetable consumption, physical activity
• social and emotional wellbeing
• medications
• health actions such as use of health services, barriers to accessing health services, and cultural safety when using some of these services
• physical measurements – blood pressure, height, weight, and waist circumference.

Information about facilities in discrete Indigenous communities was collected by interviewers using a paper-based Community Facilities Form. This data will be combined with equivalent data collected in the 2023 National Aboriginal and Torres Strait Islander Nutrition and Physical Activity Survey (NATSINPAS) and released in 2025.

The 2022–23 NATSIHS uses the Standard for Sex, Gender, Variations of Sex Characteristics and Sexual Orientation Variables, 2020. Data in this release are presented using the Sex at birth variable. When a small number of responses are recorded in any output category, outputs may be suppressed or combined into other categories due to confidentiality and statistical issues. A small number of people in the survey reported having a term other than male or female recorded as their sex at birth. Estimates for people whose sex at birth is neither male nor female are not able to be output as a separate category, but they are included in the estimates for total persons. 

For a full list of content collected, see the Data Item List in the Data downloads section.

As part of the IHMHS, respondents aged 5 years and over were asked if they would like to participate in the National Aboriginal and Torres Strait Islander Health Measures Survey (NATSIHMS). This involved voluntarily providing blood and/or urine samples (urine samples only for children aged 5–11 years) at a pathology collection centre. For some communities, visiting pathology services were arranged.

A copy of the questionnaire, prompt cards and measurements card are available on request by emailing client.services@abs.gov.au or calling 1300 135 070.

As only a sample of people in Australia were surveyed, results needed to be converted into estimates for the whole population. This was done through a process called weighting:

• Each person or household is given a number (known as a weight) to reflect how many people or households they represent in the whole population.
• A person or household’s initial weight is based on their probability of being selected in the sample. For example, if the probability of being selected in the survey was one in 45, then the person would have an initial weight of 45 (that is, they would represent 45 people).

The person weights are then calibrated to align with independent estimates of the in-scope population, referred to as ‘benchmarks’. The benchmarks use additional information about the population to ensure that:

• people in the sample represent people that are similar to them, and
• the survey estimates reflect the distribution of the whole population, not the sample.

For this survey, person weights were simultaneously calibrated to the following population benchmarks:

• state/territory by remoteness area
• state/territory by age by sex
• Torres Strait Islander status by Torres Strait Islander region by adult/child status
• remoteness area by age by sex
• state/territory by discrete Indigenous community.

The survey was benchmarked to the estimated Aboriginal and Torres Strait Islander resident population living in private dwellings at 30 June 2023 which was 993,967 persons. As people in non-private dwellings (for example, hotels) are excluded from the scope of the survey, they were also excluded from the survey benchmarks. The 2022–23 estimates do not, and are not intended to, match estimates for the total resident Aboriginal and Torres Strait Islander population obtained from other sources. This approach is consistent with the 2018–19 NATSIHS.

For household weights, the ABS does not produce counts of Aboriginal and Torres Strait Islander dwellings so household level benchmarks are not available. Instead, a household composition benchmark was calculated using the weighted person level data. 

Initial household weights were the average of the final person level weights of the respondents in the household, with an adjustment for the number of Aboriginal and Torres Strait Islander persons in the household.

Estimates of the number of households by household composition (number of adults and number of children) were produced using the weighted person level dataset. These estimates were used as household benchmarks. 

The household weights were then calibrated to the following benchmarks, derived from the weighted person dataset:

• state/territory by discrete Indigenous community by household composition
• state/territory by remoteness area by household composition.

The sum of the household weights provides an estimate of the number of Aboriginal and Torres Strait Islander households.

Undercoverage is a potential source of non-sampling error. It is the shortfall between the population represented by the achieved sample and the in-scope population. It can introduce bias into the survey estimates; however, the extent of any bias depends on the size of the undercoverage as well as the difference in the characteristics of those people in the coverage population and those of the in-scope population.

Undercoverage rates can be estimated by calculating the difference between the sum of the initial weights of the sample and the population count. If a survey has no undercoverage, then the sum of the initial weights of the sample would equal the population count (ignoring small variations due to sampling error).

In the 2022–23 NATSIHS, there was an increase in the undercoverage rate compared with previous Aboriginal and Torres Strait Islander surveys. The overall undercoverage rate was approximately 75% of the in-scope population at the national level. The estimated undercoverage in the 2018–19 NATSIHS was 67%, while in the 2012–13 NATSIHS it was 62%.

The undercoverage rate for non-community areas was 77% and for community areas was 50%. The undercoverage rate varied across the states and territories.

Given the high undercoverage rate, extensive analysis was undertaken to ensure the results were consistent with other data sources. Potential bias due to undercoverage was addressed by the application of adjustments to the initial weights and through the use of population benchmarks.

Undercoverage may occur due to a number of factors, including:

• frame exclusions (areas being removed from the sampling frame)
• non-response
• people not identifying as being of Aboriginal and/or Torres Strait Islander origin
• issues arising in the field. 

Each of the factors is explained in more detail below.

Two types of error are possible in estimates based on a sample survey: 

• non-sampling error   
• sampling error.

This release presents health estimates for the Aboriginal and Torres Strait Islander population for 2022–23.

• Commentary presents analysis of national time series data (2022–23 compared with 2018–19) and by remoteness.
• Data cubes (spreadsheets) present estimates, proportions and their associated measures of error at a national level, by remoteness and by state/territory (excluding the ACT). 
• A Data Item List is also available.
• Detailed microdata is available in DataLab for users who want to undertake interactive (real time) complex analysis of microdata in the secure ABS environment.
• The Closing the Gap: Guide to Data Specifications for the National Aboriginal and Torres Strait Islander Health Survey provides information on 2022–23 NATSIHS data items used for reporting on targets for the National Agreement on Closing the Gap.

The ABS supports a strengths-based approach when disseminating data about the Aboriginal and Torres Strait Islander population. No comparisons with the non-Indigenous population are included in this release. For advice on making comparisons, see the Non-Indigenous comparisons section. 

Additional data from the survey will be available via a range of other products and services:

• A TableBuilder product, which enables users to produce their own tables and graphs, is expected to be available via the ABS website in the first half of 2025. 
• An article (or articles), developed in partnership with an external expert if possible, exploring a high priority topic in some depth is expected to be released during 2025.
• Tables can be produced on request as a paid consultancy to meet specific information requirements (subject to confidentiality and reliability of data).

The ABS is committed to supporting Aboriginal and Torres Strait Islander communities to achieve better outcomes through well-informed policy and decisions. The ABS will promote and disseminate results from the 2022–23 NATSIHS primarily through its Engagement Managers, using a combination of activities and products to return information to Aboriginal and Torres Strait Islander peoples, communities and organisations. All Return of Information products, which includes a Storybook and fact sheets, will be added to the ABS website when available for anyone to access and use – see Engagement resources.

The Census and Statistics Act 1905 authorises the ABS to collect statistical information and requires that information is not published in a way that could identify a particular person or organisation. The ABS must make sure that information about individual respondents cannot be derived from published data.

To minimise the risk of identifying individuals in aggregate statistics, a technique called perturbation is used to randomly adjust cell values. Perturbation involves small random adjustment of the statistics which have a negligible impact on the underlying pattern. This is considered the most satisfactory technique for avoiding the release of identifiable data while maximising the range of information that can be released. After perturbation, a given published cell value will be consistent across all tables. However, adding up cell values in data cubes to derive a total may give a slightly different result to the published totals. The introduction of perturbation in published data ensures that these statistics are consistent with statistics released via services such as TableBuilder.

The ABS previously conducted the NATSIHS in 2018–19, 2012–13 and 2004–05. In addition, the 2001 National Health Survey (NHS) included an Aboriginal and Torres Strait Islander sample.

The 2022–23 and 2018–19 surveys largely employed the same methodology and survey content to allow for comparability over time. Information about differences between the various iterations of the survey can be found below.

• The Data Item List for the 2022–23 NATSIHS, available in the Data downloads section, contains information about items that can be compared between 2022–23 and 2018–19. It also indicates which items are comparable to the 2022 NHS.
• Information on the differences between the 2018–19 and 2012–13 surveys is provided in the 2018–19 NATSIHS Methodology and the 2018–19 NATSIHS Data Item List.
• Information on the differences between the 2012–13 and 2004–05 surveys is provided in the Australian Aboriginal and Torres Strait Islander Health Survey: Users' Guide, 2012–13.

Based on Census data, between 2016 and 2021, the Aboriginal and Torres Strait Islander population increased by 25.2% or 163,557 people. When comparing estimates from the 2022–23 NATSIHS with previous surveys, users should be aware of the large increase in the Aboriginal and Torres Strait Islander population and consider the impact this may have when interpreting change over time.

Care has been taken to ensure that the results of this survey are as accurate as possible. The following factors should be considered when interpreting these estimates.

• Information recorded in the survey is ‘as reported’ by respondents and may differ from information available from other sources or collected using different methodologies.
• Results from previous surveys have shown a tendency for people to under-report when asked about certain topics, such as alcohol consumption, smoking and substance use.
• Different data items were collected for different time periods. The reliability and accuracy of data are dependent on the respondent's recall.
• Seasonal effects (for example, inability to access a health service in the 2 weeks prior to interview due to roads being impassable) may have impacted questions that specify time periods.
• Some people may have provided responses they felt were expected, rather than those that accurately reflect their own situation.

For a number of survey data items, some people were unwilling or unable to provide the requested information.

• Where responses for a particular data item were missing for a person or household they were recorded in a ‘not known’, ‘not stated’ or ‘refusal’ category.
• 'Not stated’ categories have either been included in the data cubes as part of the total, or they appear as a separate category. This allows users to determine the suitability of the data for their purposes.

A person is considered to have disability if they have an impairment which restricts their everyday activities and has lasted, or is expected to last, for at least 6 months. A person with disability is classified by whether they have:

• a specific limitation with any core activities (mobility, communication and self-care)
• a specific restriction when participating in schooling or employment activities, or
• no specific limitation with core activities or restriction with schooling or employment activities.

A person has a specific limitation with a core activity if they need help from another person, have difficulty or use an aid or other equipment to perform at least one selected task. The level of limitation for each core activity is based on the amount of help a person needs with a selected task:

• profound — unable to do or always needs help with a core activity task
• severe — sometimes needs help or has difficulty with a core activity task
• moderate — does not need help but has difficulty with a core activity task
• mild — does not need help and has no difficulty, but uses aids or equipment or has other limitations with a core activity task.

A person's overall level of core activity limitation is determined by their highest level of limitation in any of these activities. For example, if a person has a profound limitation with a communication task and a moderate limitation with a self-care task, the person is categorised as having profound disability.

A person has a schooling restriction if they are aged between 5 and 20 years and, because of their disability, they:

• are not attending school/undertaking further study
• need time off school or study
• attend special classes or a special school, or
• have other related difficulties.

Specifying that a schooling restriction only applies to those aged between 5 and 20 years is new for the 2022–23 NATSIHS and brings the data into alignment with the ABS standard. 

A person has an employment restriction if, because of their disability, they:

• are restricted in the type of job they could do
• are restricted in the number of hours they can work
• have difficulty finding suitable work
• need time off work, or
• are permanently unable to work.

A person with a ‘schooling/employment restriction only' is someone who reported no limitations with any of the core activities but reported having difficulty with schooling and/or employment activities.

Information was collected using the short-form version of the questions used in the ABS’ monthly Labour Force Survey.

Questions in the 2022–23 NATSIHS employment module referred to the Community Development Program (CDP). The labour force status of a person on the CDP depended on who paid for the work they did.

• If they reported they were paid by an employer or another source, they were considered employed.
• If they reported they were paid by Centrelink or were unpaid, they were considered either unemployed or not in the labour force. They were asked further questions to determine their final labour force status.

‘Family composition’ is created through the relationships that exist between a single ‘responsible adult’ and each other member of that family living in the household. Family composition is then allocated based on whether the types of relationships given below are present or not in the family, in the following order of precedence.

• A couple relationship is defined as a registered or de facto marriage, including same-sex relationships.
• A parent-child relationship is defined as a relationship between two persons usually resident in the same household. The child is attached to the parent via a natural, adoptive, step, foster or child dependency relationship.
• A child dependency relationship is defined as including all children under the age of 15 years (whether related or unrelated to the family reference person) and those natural, step, adopted or foster children who are full-time students aged 15–24 years.
• Other relationship is defined as including all those persons related by blood or by marriage who are not covered by the above relationships.

The definition of family used for the 2022–23 NATSIHS is a more restrictive definition than the ordinary notion of the term ‘family’ which generally includes relatives whether they live together or not. This reflects the need to place some physical bound on the extent of family for the purposes of being able to collect family data in surveys.

A long-term health condition is defined as a medical condition (illness, injury or disability) that was current at the time of the interview and has lasted, or is expected to last, for 6 months or more.

Information on specific health conditions was collected in individual modules, as well as a general long-term health conditions module. Questions varied to take into account differences between non-remote and remote populations and demographic characteristics. Respondents could report multiple health conditions.

Some reported conditions were assumed to be long-term, including asthma, arthritis, cancer, osteoporosis, diabetes mellitus, sight problems, rheumatic heart disease, heart attack, angina, heart failure and stroke. Diabetes mellitus, rheumatic heart disease, heart attack, angina, heart failure and stroke were also assumed to be current.

When counting the number of chronic conditions a person has, multiple conditions belonging to the same condition type are treated as the one condition. For example, a person reporting anxiety and depression is counted as having one chronic condition as they are both of the same condition type (mental and behavioural conditions).

The classification hierarchy used in the 2022–23 NATSIHS has been updated since the 2018–19 NATSIHS. It is based on the 10th revision of the International Classification of Diseases and Related Health Problems (ICD-10). New COVID-19 codes have been included in the classification, in line with the World Health Organisation's adaptation of the ICD. The conditions classification used in the 2022–23 NATSIHS is consistent with other ABS surveys, including the 2022 NHS. For more information about the conditions classification used, see the Data Item List in the Data downloads section. 

It is expected that conditions specifically mentioned in questions or shown on prompt cards would have been better reported than conditions for which responses relied entirely on a respondent’s judgement and willingness to report them.

For the 2022–23 NATSIHS, some conditions were added or removed from prompt cards which may have impacted their reported prevalence. In the long-term health conditions module, endometriosis and polycystic ovary syndrome (PCOS) were added to the prompt card, and emphysema and epilepsy were removed. Conditions which do not appear on a prompt card can still be reported by respondents to their interviewer.

The removal of emphysema in particular may have contributed to some of the decline observed in the number of persons reporting this condition for 2022–23. Emphysema is one of the conditions included in the broader chronic obstructive pulmonary disease (COPD) grouping. Estimates for COPD are not directly comparable with previous NATSIHS surveys due to this change.

Equivalised income

Differences in household types and compositions, and their requirements relative to income, can be taken into account by the application of equivalence scales. These scales are a set of ratios which, when applied to the income of different household or income unit types, produce standardised estimates of income which reflect the households' relative well-being. The modified Organisation for Economic Co-operation and Development (OECD) equivalence scale (1994) was used.

Equivalised income is derived by calculating an equivalence factor and then dividing income by that factor. The equivalence factor is built up by allocating points to each person in the household unit and summing those points. One point is allocated to the first adult in the unit, 0.5 points for each other person aged 15 years and over, and 0.3 points for each person aged less than 15 years. For example:

• a single person household has a factor of one, so equivalised income is therefore the same as reported income
• a household comprising 2 adults and a child aged less than 15 years would have a factor of 1.8, so equivalised income for this household is therefore the household income divided by 1.8.

Equivalised income is available in dollar amounts and deciles.

Income deciles

In the 2022–23 NATSIHS, the deciles for both household and personal income were not taken from the deciles within the survey. Instead, a national figure which includes both non-Indigenous and Aboriginal and Torres Strait Islander households was used, meaning each decile may not necessarily contain 10% of the in-scope population. The decile boundaries from the 2022 NHS were used and adjusted for inflation using the Consumer Price Index to account for the enumeration period difference between the 2022 NHS and the 2022–23 NATSIHS. This is a similar approach to that used in the 2018–19 NATSIHS.

The dollar amount cut-offs for household and personal income deciles are available in the Data Item List in the Data downloads section. 

Income quintiles were created by combining deciles, meaning each quintile may not contain 20% of the in-scope population.

Information about medication use was only collected in non-remote areas. Interviewers recorded the Australian Register of Therapeutic Goods Administration (TGA) identification number of each medication taken by the respondent in the last 2 weeks. These were either:

• AUST R medicines – all prescription medications and many over-the-counter products such as those used for pain relief, coughs and colds and antiseptic creams, or
• AUST L medicines – generally lower risk self-medication products, which include vitamins, minerals, and herbal and homoeopathic products.

For medications without an AUST R or AUST L code (for example, medications obtained overseas), interviewers were able to record details of the medication which were later coded by office staff. Up to 50 different medications were able to be recorded.

Therapeutic substances reported were coded as either medications or dietary supplements.

• Medications were coded to the fourth level of the 2023 Index of the World Health Organisation’s Anatomical Therapeutic Chemical (ATC) classification system based on their active ingredient(s) and their therapeutic application.
• Dietary supplements were coded to a classification adapted from the Australian Food, Supplement and Nutrient Database (AUSNUT) food classification by Food Standards Australia New Zealand (FSANZ). The classification is identical to that used in the 2018–19 NATSIHS.

The categorisation of substances as either medications or dietary supplements has been adopted for the purposes of describing data collected in the survey and should not be assumed to be an exact description of the contents of either category. For example, while the ATC includes codes for vitamins and minerals and other dietary supplements, such supplements were coded to the FSANZ supplements classification.

In this survey, dietary supplements included:

• vitamins
• minerals
• herbal extracts (including Chinese herbs)
• amino acids
• omega 3 fatty acids
• other fatty acids
• glucosamine/chondroitin formulations.

The collection method for this topic varied between non-remote and remote areas.

• In non-remote areas, respondents had the option to answer the questions using a self-completed computer-based questionnaire.
• In remote areas, respondents were asked the questions by an interviewer.

Substance use is likely to be under-reported.

• Responses to these questions were voluntary, with respondents able to not answer some or all of the questions.
• The potentially sensitive and personal nature of the questions may have impacted on people’s willingness to respond and what responses they provided.
• Under-reporting of substance use may be more common in remote areas as people provided their responses directly to the interviewer and may have had other household members present at the interview.
• The extent to which under-reporting has occurred is not able to be quantified.

Alcohol consumption risk levels have been assessed based on an interpretation of both the 2020 and 2009 National Health and Medical Research Council (NHMRC) Australian guidelines to reduce health risks from drinking alcohol.

Data for the 2020 guidelines cannot be directly compared to data for the 2009 guidelines.

The NHMRC guidelines recommend children and young people under 18 years of age should not drink alcohol. In this survey, people aged 15–17 years are assessed against the relevant adult guidelines to provide an estimate of the level of risk for this age group. 

2020 Guideline

In this survey, a person was considered to have exceeded the Australian Adult Alcohol Guideline if they had consumed:

• more than 10 standard drinks in the last week (component A), and/or 
• more than 4 standard drinks on at least 12 days in the last 12 months (component B).

For component A, it was assumed the level of alcohol consumption in the last week was typical. A person’s estimated total weekly consumption was derived from information provided by the person about:

• the number, type and serving sizes of alcoholic drinks consumed on (up to a maximum of) the 3 most recent days alcohol was consumed in the week prior to interview, and
• the total number of days alcohol was consumed that week.

It was derived by:

• calculating the total amount of alcohol consumed (in mLs) for each drink type by multiplying the alcohol content (%) by the volume (mL), based on the type (for example, light beer, red wine), and number of drinks reported on the maximum of 3 most recent days alcohol was consumed in the previous week
• summing the drink type results to derive the total alcohol consumption for the maximum of 3 most recent days alcohol was consumed
• dividing that result by the number of days on which alcohol consumption was reported (that is, by one, two or three) to derive average daily alcohol consumption for those days, and
• multiplying that daily average by the total number of days alcohol was consumed that week to determine the estimated total weekly consumption.

Component B was assessed using a person’s response to questions about the number of times in the last 12 months they had consumed 5 or more standard drinks in one day. The number of standard drinks was as reported by the person. This is different to component A, where the number of standard drinks was derived from information about the number, type and serving size of drinks consumed.

2009 Guidelines

For information about how alcohol consumption risk levels were assessed using the 2009 Guidelines, refer to Appendix – Assessing health risk factors from the 2018–19 NATSIHS. 

People aged 18 years and over were asked to provide a blood pressure reading, voluntarily collected at the time of interview. Readings were categorised as:

• normal — less than 120/80 mmHg (millimetres of mercury)
• normal-high — from 120/80 to less than 140/90
• high — from 140/90 to less than 160/100
• very high — from 160/100 to less than 180/110
• severe — from 180/110.

People were placed in the highest of the categories that either the systolic or diastolic reading fell into.

A reading of 140/90 mmHg or higher does not necessarily indicate a person has hypertension. In this survey, hypertension is defined as a condition that has lasted, or which the respondent expects to last, for 6 months or more.

The reading also does not take into account whether a person might have had a high blood pressure reading if they were not managing it through the use of medication.

Breastfeeding of children aged 3 years and under was assessed using the National Health and Medical Research Council's 2012 Infant Feeding Guidelines. The guidelines recommend infants:

• be exclusively breastfed to around 6 months of age (the 6 month guideline)
• continue to be breastfed with appropriate complementary foods until at least 12 months of age (the 12 month guideline).

The 6 month guideline was considered to have been met if a child had been exclusively breastfed for at least 6 months. Children under the age of 6 months were excluded.

The 12 month guideline was considered to have been met if a child was exclusively breastfed for at least 6 months and then continued to be breastfed to 12 months of age. Children under the age of 12 months were excluded.

If unable to determine whether a child was exclusively breastfed for 6 months, or exclusively breastfed for 6 months then continued to be breastfed to 12 months of age, they were classified as not known.

In this survey, the food security status of a household was based on whether one or more members of the household had enough food, or money to buy the food, needed for an active, healthy life at all times in the last 12 months. This was assessed using a set of 10 questions, known as the Adult Food Security Survey Module, developed by the United States Department of Agriculture (USDA). 

• The questions were asked of a household spokesperson aged 18 years or over, on behalf of all members of the household.
• The specific experiences of children in the household do not form part of this measure. 
• Minor modifications were made to the wording used in some questions to improve their ability to be understood and interpreted in the Australian context.

Households were asked 3 questions to establish whether there were any indicators of food insecurity. If at least one question was answered in the affirmative, households were asked further questions to establish the severity of food insecurity. Households were scored 1 for each affirmative response to give a total score between 0 and 10.

Non-response to individual questions varied, ranging from 0.1% to 2.3%. Around 5% of households had at least one missing response and required responses to be imputed. Missing values were imputed based on the household’s responses to other questions using the USDA’s direct imputation method. An affirmative response was imputed only if a household indicated it had experienced all of the less severe types of food insecurity and also experienced a more severe type of food insecurity. A small proportion of households (0.8%) that did not answer all of the first 3 questions did not have missing values imputed and were unable to be classified.

Households were then classified as having experienced food security or marginal, moderate or severe food insecurity based on their total score. Following consultation with Australian food security experts, the ABS adopted Statistics Canada’s approach to classifying households. This differs from the USDA approach by:

• classifying a score of 2 as moderate food insecurity instead of marginal food insecurity, and
• classifying marginal food insecurity as food insecure instead of food secure. 

The food security status assigned to a household may not reflect the experience of each individual within the household.

Fruit and vegetable consumption was assessed using the National Health and Medical Research Council’s (NHMRC) 2013 Australian Dietary Guidelines. The guidelines recommend consumption of a minimum number of serves of fruit and vegetables each day, depending on a person's age and sex. Consumption was assessed using a respondent's reported usual daily intake in serves of fruit and vegetables. All drinks, beverages and juices were excluded. 

A serve of fruit is approximately 150 grams of fresh fruit or 30 grams of dried fruit. A serve of vegetables is approximately half a cup of cooked vegetables (including legumes) or one cup of salad vegetables – equivalent to approximately 75 grams. Tomatoes were included as vegetables.

In this survey, physical activity undertaken by people living in non-remote areas has been assessed based on an interpretation of the 2014 Australia's Physical Activity and Sedentary Behaviour Guidelines.

Guidelines for people aged 15–17 years

People aged 15–17 years were considered to have met the guidelines if, in the last week, they did:

• one or more of the following for at least 60 minutes every day: walking for exercise, recreation or sport for 10 minutes or more, walking to get to places for 10 minutes or more, moderate physical activity, or vigorous physical activity, and
• at least one minute of vigorous physical activity as part of their total activity in the last week, and
• strength or toning activities during moderate or vigorous physical activity (excluding activity in the workplace) on at least 3 days. 

Guidelines for people aged 18–64 years

People aged 18–64 years were considered to have met the guidelines if, in the last week, they:

• did one or more of the following on at least 5 days: walking for exercise, recreation or sport for 10 minutes or more, walking to get to places for 10 minutes or more, moderate physical activity, or vigorous physical activity, and
• accumulated at least 150 minutes of any combination of the above (for this age group, every minute spent on vigorous physical activity is counted as 2 minutes for the purpose of determining whether the person met this component), and
• did strength or toning activities during moderate or vigorous physical activity (excluding activity in the workplace) on at least 2 days.

Guidelines for people aged 65 years and over

People aged 65 years and over were considered to have met the guidelines if, in the last week, they did:

• one or more of the following every day: walking for exercise, recreation or sport for 10 minutes or more, walking to get to places for 10 minutes or more, moderate physical activity, or vigorous physical activity, and
• any combination of the above for at least 30 minutes on at least 5 days.

People aged 15 years and over were asked about the extent to which they were regularly smoking tobacco products and using e-cigarettes/vaping at the time of interview.

Tobacco products include:

• manufactured (packet) cigarettes
• roll-your-own cigarettes
• pipes, cigars or other tobacco products.

Tobacco products exclude:

• chewing tobacco
• smoking of non-tobacco products (such as marijuana).

A person’s smoker status for tobacco products was categorised as:

• current daily smoker — a person who reported they regularly smoked one or more cigarettes, pipes, cigars or other tobacco products per day
• current smoker less than daily — a person who reported they smoked cigarettes, pipes, cigars or other tobacco products less frequently than daily
• ex-smoker — a person who reported they did not currently smoke but had either previously regularly smoked daily, smoked at least 100 cigarettes in their lifetime, or smoked pipes, cigars or other tobacco products at least 20 times in their lifetime
• never smoked — a person who reported they had never regularly smoked daily, smoked less than 100 cigarettes in their lifetime, and smoked pipes, cigars or other tobacco products less than 20 times in their lifetime.

For e-cigarette/vaping devices (with or without nicotine), people were asked whether they had ever used these products and, if they had, whether they were currently using them.

The e-cigarette/vaping device data is not comparable with similar data from the 2018–19 NATSIHS due to a change in the collection method.

Waist circumference is a measurement, in centimetres (cm), of a person’s waist. Measurements were voluntarily provided by people aged 2 years and over at the time of interview. Respondents took their own measurements using a tape measure (maximum 150cm). People who advised they were pregnant were not asked to provide measurements.

The waist circumferences of people aged 18 years and over were classified by level of risk of developing chronic disease as recommended by the World Health Organization’s 2008 Waist Circumference and Waist-Hip Ratio: Report of a WHO Consultation.

Respondents were presented with a list of mental and behavioural conditions on a prompt card. They were asked whether they had been diagnosed with any of the listed conditions by a health professional, followed by questions on whether those conditions were still current and whether they had lasted, or were expected to last, for 6 months or more.

Results from the 2022–23 NATSIHS are generally comparable with the 2018–19 NATSIHS. 

Social and emotional wellbeing was measured using several short series of questions taken from existing health and wellbeing surveys. Respondents aged 15 years and over and present at the interview were asked these questions. These questions could not be answered by someone else on the respondent’s behalf.

• Two sets of questions asked about the frequency of specific feelings in the 4 weeks prior to interview to measure psychological distress and positive emotional states.
• People in non-remote areas were asked two additional sets of questions about levels of mastery (the sense of control over one’s life) and perceptions of social support.

The in-scope population for these questions changed from persons aged 18 years and over in the 2018–19 NATSIHS to persons aged 15 years and over. Comparisons with the 2018–19 NATSIHS should be limited to persons aged 18 years and over.

These questions are explained in more detail below.

Several other questions were asked of respondents aged 15 years and over and present at the interview to determine:

• the impact of psychological distress on employment and other regular activities
• how often physical health problems had been the main cause of psychological distress
• use of health and community services, such as doctors and counsellors, for mental health
• barriers to using health services for mental health

New questions were introduced in 2022–23 which asked respondents about which health services they had either accessed for mental health in the last 12 months, or wanted to seek support from but didn’t, and the reasons for not seeking support from these services.

In the 2022–23 NATSIHS, measurements of height, weight and waist circumference were voluntarily provided by respondents aged 2 years and over, whilst blood pressure measurements were also voluntarily provided by respondents aged 18 years and over. Measurements were not provided by respondents who advised they were pregnant. These measurements provide information on overweight and obesity (using Body Mass Index (BMI)), risk of developing chronic disease, and high blood pressure amongst the Aboriginal and Torres Strait Islander population.

For information on how respondents were classified based on these measurements, see the Assessing health risk factors section.

Physical measurements have a relatively high rate of non-response due to their voluntary and sensitive nature. To correct for the high rate of non-response, values were imputed for those that did not provide measurements to achieve estimates of physical measurements for the whole population.

Non-response rates for physical measurements were higher in the 2022–23 NATSIHS than the 2018–19 NATSIHS.

The higher non-response rates could in part be due to the trend of declining participation in physical measurements. The COVID-19 pandemic may also have had an effect. The procedures for collecting physical measurements in the 2022–23 NATSIHS were adapted to include increased hygiene and social distancing measures, and respondents needed to take their own measurements rather than ABS interviewers taking the measurements.

In addition to the voluntary measured items, people aged 2 years and over were asked to self-report their height and weight measurements. People who advised they were pregnant were not asked. Of those whose measured height and/or weight was not provided, 63.5% of adults aged 18 years and over and 48.5% of children aged 2–17 years provided both self-reported height and weight measurements. This provides valuable information about height and weight that can be used in assisting in the imputation for those with missing values.

Missing values were imputed using 'hot deck' imputation. In this method, a record with a missing response (the 'recipient') receives the response of another similar record (the 'donor'). A number of characteristics with which to match recipients to donors were used. For adults aged 18 years and over they were:

• age group
• sex
• part of state (capital city and balance of state) by remoteness (non-remote and remote areas) 
• self-reported BMI category (calculated from self-reported height and weight)
• self-perceived body mass (underweight, acceptable, or overweight)
• level of exercise (sedentary, low, moderate, or high) for non-remote respondents only
• whether or not has high cholesterol (as a long-term health condition).

For example, a female recipient aged 35–39 years who lives in a capital city, has a self-reported BMI category of overweight, has a self-perceived body mass of acceptable, has high cholesterol and lives a sedentary lifestyle will match to a donor record who has the same profile (female, 35–39 years, self-reports as overweight, and so on).

For children aged 2–14 years, the following variables were used:

• single year of age
• sex
• self-reported BMI category
• part of state by remoteness. 

For children aged 15–17 years, the same imputation variables were used as for children aged 2–14 years, in addition to level of exercise for non-remote respondents. Cholesterol data was not collected for persons under 18 years of age so could not be used as an imputation variable. 

For BMI, 68.6% of imputed records matched to a donor record using all variables. The remaining 31.4% were matched using fewer variables.

Imputation was not performed for people who self-reported pregnancy as they are not applicable to the BMI population for analysis. 

All physical measurements data that includes imputed values (BMI, waist circumference and blood pressure) are of suitable quality for comparisons with the 2018–19 NATSIHS. For comparisons with earlier surveys, the ABS recommends comparing proportions only, as imputation was not used prior to the 2018–19 NATSIHS.

The ABS supports a strengths-based approach when disseminating data about the Aboriginal and Torres Strait Islander population. No comparisons with the non-Indigenous population are included in this release.

However, the ABS acknowledges some users may want to compare the NATSIHS data for the Aboriginal and Torres Strait Islander population with data for the non-Indigenous population from other surveys, such as the National Health Survey.

The Aboriginal and Torres Strait Islander population has a younger age structure than the non-Indigenous population. Age is strongly related to many population characteristics, such as long-term health conditions and employment patterns. To account for this, the ABS uses a technique called age standardisation to produce proportions that can be used for comparison purposes. Age standardised estimates of prevalence are those rates that ‘would have occurred’ should both the Aboriginal and Torres Strait Islander and non-Indigenous populations have the same age composition.

The ABS recommends any comparisons between the Aboriginal and Torres Strait Islander population and the non-Indigenous population for characteristics which are associated with age are done using age standardised estimates. Age standardised estimates are not required when making comparisons by age group (for example, 18–24 years).

Age standardised estimates can be produced on request by the ABS as a paid consultancy – see Consultancy request form for more information.