National Health Survey methodology

The 2022 National Health Survey (NHS) 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 NHS was conducted from January 2022 to April 2023. Data was collected from approximately 13,100 households around Australia.

The survey focused on the health status of Australians and health-related aspects of their lifestyles. Information was collected about respondents' long-term health conditions and on lifestyle 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. In addition to the self-reported measures, respondents could voluntarily provide blood pressure, height, weight and waist measurements.

Some topics were included for the first time in the 2022 NHS, including questions about gender and sexual orientation and use of over the counter medications. 

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

The 2022 NHS is considered to be comparable with the 2017–18 NHS and previous cycles. The 2022 NHS will not be compared to the 2020–21 survey which was enumerated during the COVID-19 pandemic with significant changes to the data collection. The 2020–21 survey is considered a break in time series from previous NHS collections, to be used for point-in-time national analysis only.

Key changes to the survey in 2022 compared with the 2017–18 NHS are detailed in Summary of content changes. This includes updates to the classification of long-term health conditions (refer to Health conditions for more details). Changes to the 2022 NHS from the 2020–21 NHS are also included for completeness. 

The scope of the survey included:

• all usual residents in Australia aged 0 years and over living in private dwellings.
• both urban and rural areas in all states and territories, except for very remote parts of Australia and discrete Aboriginal and Torres Strait Islander communities.
• members of the Australian permanent defence forces living in private dwellings and any overseas visitors who have been working or studying in Australia for the last 12 months or more, or intend to do so.

The following people were excluded:

• visitors to private dwellings.
• overseas visitors who have not been working or studying in Australia for 12 months or more, or do not intend to do so.
• members of non-Australian defence forces stationed in Australia and their dependants.
• non-Australian diplomats, diplomatic staff and members of their households.
• people who usually live in non-private dwellings, such as hotels, motels, hostels, hospitals, nursing homes and short-stay caravan parks (people in long-stay caravan parks, manufactured home estates and marinas are in scope).
• people in Very Remote areas.
• discrete Aboriginal and Torres Strait Islander communities.
• households where all Usual Residents are less than 18 years of age.

Households could complete the first part of the survey, which collected basic demographic information about all usual residents of the household via an online form, telephone interview or face-to-face interview with an ABS Interviewer. The individual questionnaires were completed via face-to-face interview only.

Households were randomly selected to participate in the survey. One adult aged 18 years and over and one child aged 0–17 years were randomly selected to complete individual questionnaires.

If the randomly selected child was aged 0–14 years a parent/guardian answered the questions on the child’s behalf.

If the randomly selected child was aged 15–17 years, parental/guardian consent was sought for the selected child to answer the questions. Where consent was not given a parent/guardian answered the questions on the selected person’s behalf. 

Proxy interviews were accepted for selected adults who were unable to answer for themselves due to language difficulties, significant long term illness or disability.

There were 13,095 fully responding households in the survey, a response rate of 56.7%. The following table summarises the response rates achieved for the sample approached across Australia.

The survey collected the following content:

• Demographics – Age, Sex, Gender and Sexual orientation, Country of Birth, Main language spoken, Marital status
• Household details – Type, Size, Household composition, Tenure, SEIFA, Geography
• Labour force status
• Educational attainment
• Personal and Household Income
• Migrant and Visa status
• Self-assessed health status
• Self-reported height and weight
• Long-term health conditions such as arthritis, asthma, cancer, diabetes, hypertension, kidney disease etc
• Risk factors such as tobacco smoking, e-cigarettes/vaping, alcohol consumption, fruit and vegetable consumption, and physical activity
• Bodily pain
• Psychological distress
• Physical Measures – blood pressure, height, weight, and waist

The 2022 NHS uses the Standard for Sex, Gender, Variations of Sex Characteristics and Sexual Orientation Variables, 2020. Data in this publication 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 study 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 or female are not able to be output as a separate category but they are included in the estimates for total Persons. 

See the Data Item List for full details of content collected in the 2022 NHS.

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

Benchmarks align to the estimated resident population (ERP) at September 2022 which was 10,029,883 households and 25,433,341 people (after exclusion of people living in non-private dwellings, very remote areas of Australia and discrete Aboriginal and Torres Strait Islander communities).

Sample counts and weighted estimates are presented in the table below. 

This release presents national health estimates for 2022. Commentary presents analysis by age groups, sex, state and selected population characteristics.

Data Cubes (spreadsheets) in this release present tables of estimates, proportions and their associated measures of error. A data item list is also available.

Detailed microdata is also available on DataLab for users who want to undertake interactive (real time) complex analysis of microdata in the secure ABS environment.

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 publications ensures that these statistics are consistent with statistics released via services such as TableBuilder.

The following table summarises content changes applied in the 2022 NHS. For full details of data items refer to the Data Item List.

The 2022 NHS is considered to be comparable to the 2017-18 NHS and previous cycles. The 2020–21 NHS data should be considered a break in time series from previous NHS collections and used for point-in-time national analysis only. The survey was collected during the COVID-19 pandemic which significantly changed the data collection. Changes to the 2022 NHS from the 2020–21 NHS are included here for completeness. 

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

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

Any reported health conditions that did not meet this definition were excluded from estimates, e.g. a person may have been told that they had a health condition in the past but it is no longer current or expected to last 6 months or more.  Conditions that were not considered to be current and long term can be analysed using the data item Condition Status (CONDSTAT) on the survey microdata.

The classification hierarchy is based on the 10th revision of the International Classification of Diseases (ICD). The classification was updated for the previous cycle, 2020–21 NHS, to improve use of the conditions data.

New COVID-19 codes have been included in the classification for the 2022 NHS, in line with the World Health Organisation's adaptation of the ICD.

See the Data Item List for full details of the conditions classification used in the 2022 NHS. 

A concordance for the current classification to the previous version used in the 2017–18 NHS is available on request.

Alcohol consumption risk levels have been assessed using guidelines from the National Health and Medical Research Council (NHMRC) released from 2009 and updated in 2020.

Analysis in the commentary of the 2022 NHS has focussed on assessing alcohol consumption against the updated 2020 guideline. However, data has been provided in the Data Cubes to assess against the 2009 guidelines to provide a closure of this analysis. Analysis of the updated 2020 guidelines cannot be directly compared to the 2009 guidelines and therefore represents a break in time series.

Current 2020 guidelines

The most recent Australian Adult Alcohol Guideline, released by NHMRC in December 2020, is based on Guideline 1 of the Australian Guidelines to Reduce Health Risks From Drinking Alcohol. Guideline 1 recommends that ‘to reduce the risk of harm from alcohol-related disease or injury, healthy men and women should drink no more than 10 standard drinks a week and no more than 4 standard drinks on any one day. The less you drink, the lower your risk of harm from alcohol’. Persons aged 18 years and over who exceeded the Guideline have been interpreted as those who either consumed more than 10 standard drinks per week, or more than 4 standard drinks on a single day, or both components (i.e. groups A, B or C) (see the table below). The guidelines aim to reduce the risk of dying from alcohol-related disease and injury. Adults who drink within the Guideline recommendation have a less than 1 in 100 chance of dying from an alcohol-related condition (i.e. group D).

Additional advice was received that consuming more than 4 standard drinks on any day at least monthly in the last year was an appropriate measure in line with NHMRC recommendations. This means that those who consumed more than 4 standard drinks on any day at least monthly are considered to have exceeded the 1 in 100 chance of dying from an alcohol-related condition. This survey measures monthly consumption as consuming 5 or more drinks at least 12 or more times in the last 12 months. This measure is not directly comparable to single occasion risk interpreted from the NHMRC 2009 Guideline 2.

Guideline 2 recommends that ‘to reduce the risk of injury and other harms to health, children and young people under 18 years of age should not drink alcohol’. That is, not consuming alcohol is the safest option. However, this population group has been assessed in the NHS against the Australian Adult Alcohol Guideline. This allows for assessment of the levels of risky drinking for this age group. Data presented for people aged 15–17 years in this release does not reflect guideline 2.

For more detailed information, see Australian guidelines to reduce health risks from drinking alcohol.

Previous 2009 Alcohol guidelines

The 2009 lifetime risk guideline (guideline 1) recommended no more than 2 standard drinks per day (equivalent of 14 standard drinks per week). This guideline was assessed using average daily consumption of alcohol for persons aged 15 years and over, derived from the type, number and serving sizes of beverages consumed on the three most recent days of the week prior to interview, in conjunction with the total number of days alcohol was consumed in the week prior to interview.

The 2009 single occasion risk guideline (guideline 2) recommended no more than 4 standard drinks on a single occasion. This guideline was assessed using questions on the number of times in the last 12 months a person's consumption exceeded specified levels.

Physical activity refers to a combination of exercise and workplace activity. Exercise includes walking, running and bike riding for transport or fitness; sport or recreation; moderate exercise and/or vigorous exercise undertaken in the last week. Workplace activity is physical activity undertaken in the workplace which includes moderate and/or vigorous activity undertaken on a typical workday.

Australia’s Physical Activity and Sedentary Behaviour Guidelines 2014, are assessed against the respective age group for NHS data.

The 2014 Guidelines recommend that:

• Children and young people (5–17 years) accumulate at least 60 minutes of moderate to vigorous physical activity every day, from a variety of activities including some vigorous, and do muscle strengthening activities on at least three days each week 
• Adults (18–64 years) should be active most days of the week, accumulate 150 to 300 minutes of moderate intensity physical activity or 75 to 150 minutes of vigorous intensity physical activity (or an equivalent combination each week), and do muscle strengthening activities on at least two days each week
• Older Australians (65 years and over) should accumulate at least 30 minutes of moderate intensity physical activity on most, preferably all, days.

Minutes undertook physical activity is based on respondents meeting the recommended guideline of at least 150 minutes of physical activity a week. Minutes spent on vigorous activity is multiplied by a factor of two.

For more information, see Australia's Physical Activity and Sedentary Behaviour Guidelines.

A balanced diet, including sufficient fruit and vegetables, reduces a person's risk of developing conditions such as heart disease and diabetes. The National Health and Medical Research Council's (NHMRC) 2013 Australian Dietary Guidelines recommend a minimum number of serves of fruit and vegetables each day, depending on a person's age and sex, to ensure good nutrition and health. Adequacy of intake (consumption) is based on whether a respondent's reported usual daily intake in serves of fruit or vegetables meets or exceeds each recommendation.

Usual daily intake of fruit refers to the number of serves of fruit (excluding drinks and beverages) usually consumed each day, as reported by the respondent. A serve is approximately 150 grams of fresh fruit or 50 grams of dried fruit. Adequate daily fruit intake refers to whether the respondent met the minimum number of serves as recommended in the NHMRC 2013 Australian Dietary Guidelines. 

Usual daily intake of vegetables refers to the number of serves of vegetables (excluding drinks and beverages) usually consumed each day, as reported by the respondent. A serve is approximately half a cup of cooked vegetables (including legumes) or one cup of salad vegetables – equivalent to approximately 75 grams. Adequate daily vegetable intake refers to whether the respondent met the minimum number of serves as recommended in the NHMRC 2013 Australian Dietary Guidelines. Tomatoes were included as vegetables while juices were excluded.

For more information, see the National Health and Medical Research Council (NHMRC) 2013 Australian Dietary Guidelines. 

In the 2022 National Health Survey (NHS), voluntary measurements of height, weight and waist circumference were collected from respondents aged two years and over (respondents who advised that they were pregnant were not measured), whilst voluntary blood pressure measurements were also collected from adult respondents (aged 18 years and over). These measurements provide information on overweight and obesity (using Body Mass Index (BMI)), risk of developing chronic disease, and high blood pressure amongst the Australian population.

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, imputation of values for those that did not have measurements collected was used to achieve estimates of physical measurements for the whole population.

Non-response rates for physical measurements were higher in 2022 than in the 2017–18 NHS (which in turn were higher than the 2014–15 NHS). The non-response for BMI for adults in 2022 was 40.8%, compared with 33.8% in 2017–18 and 26.8% in 2014–15. The non-response for BMI for children 2022 was 56.8%, compared with 43.9% in 2017–18 and 37.7% in 2014–15.

The non-response for waist measurements in 2022 was 39.4% for adults and 57.6% for children. The non-response for Blood Pressure measurements (taken for adults only) in 2022 was 39.0%.

The higher non-response rates in 2022 could in part be due to the trend of declining participation in physical measures, however the COVID-19 pandemic would also have had an effect. The procedures for collecting physical measurements in the 2022 NHS were adapted to include increased hygiene and social distancing measures, and respondents were required to take their own measurements (rather than ABS Interviewers taking measurements).

In addition to the voluntary measured items, respondents in the 2022 NHS were also asked to self report their height and weight measurements (respondents who advised that they were pregnant were not asked to self-report as they are not applicable to the BMI population for analysis). This provides valuable information about height and weight that can be used in assisting in the imputation for those with missing values.

In the 2022, 2017–18 and 2014–15 NHS, missing values were imputed using the 'hot decking' imputation method. 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 they were:

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

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

For BMI, around 85% of imputed records with self-reported BMI used all seven variables to match to a donor record. The remaining 15% could not be matched using all seven variables and were therefore matched using fewer variables.

For children 2–14 years, single year of age, sex, self reported BMI and part of state were used as imputation variables, while for 15–17 year olds, level of exercise and self-perceived body mass (only if a person answered for themselves) were also used as imputation variables, due to the other variables not being collected for children aged 2–17 years. Single year of age was used in the imputation method for children in the 2022 NHS, which differs from the 2017–18 NHS. This change to the methodology was made for the 2018–19 National Aboriginal and Torres Strait Islander Health Survey (NATSIHS) and retained for NHS22, as children's height and weight can change rapidly within a short period of time and, to avoid over or under estimating BMI, donors that were of the same age as the recipient were used. 

Sex was not used as a variable to match recipients to donors for people with a Transgender and Gender Diverse experience. People with a Transgender and Gender Diverse experience did not act as donors during the imputation process. Imputation was not performed for people who self-reported pregnancy as they are not applicable to the BMI population for analysis.  

Physical measurement data (BMI, waist circumference and blood pressure) that includes imputed values are of suitable quality for comparisons to 2017–18 and 2014–15 NHS. For comparisons to earlier years, the Australian Bureau of Statistics (ABS) recommends using proportion comparisons only as imputation was not used on the physical measurement data prior to 2014–15 NHS.

Age standardisation is a way of allowing comparisons between two or more populations with different age structures, in order to remove age as a factor when examining relationships between variables. For example, the age structure of the population of Australia is changing over time. As the prevalence of a particular health condition (for example, arthritis) may be related to age, any increase in the proportion of people with that health condition over time may be due to real increases in prevalence or to changes in the age structure of the population over time or to both. Age standardising removes the effect of age in assessing change over time or between different populations.

Proportions quoted in commentary in this publication are not age standardised, however, proportions presented in Tables 1 and 2 include age standardised rates. Data are age standardised to the 2001 Australian population.

The Kessler Psychological Distress Scale (K10) is a widely used indicator, which gives a simple measure of psychological distress. It is not a diagnostic tool but is an indicator of psychological distress.

The K10 is based on a person's emotional state during the 4 weeks prior to the survey interview. People were asked a series of 10 questions, about how often they felt:

1. tired for no good reason
2. nervous
3. so nervous nothing could calm them down
4. hopeless
5. restless or fidgety
6. so restless that they could not sit still
7. depressed
8. that everything was an effort
9. so sad that nothing could cheer them up; and
10. worthless.

For each question, an answer was provided using a five-level response scale, based on the amount of time a person reported experiencing the problem. The response scale corresponded to the following:

• none of the time
• a little of the time
• some of the time
• most of the time
• all of the time.

If a person selected 'none of the time' for questions 2 or 5 they were not asked the follow-on questions at 3 or 6 but were skipped to subsequent questions at 4 or 7 respectively.

Scores for the 10 questions were put together, with a minimum possible score of 10 and a maximum possible score of 50. Low scores indicate low levels of psychological distress, and high scores indicate high levels of psychological distress.  In this publication, scores are grouped as follows:

• Low levels of distress (10–15);
• Moderate levels of distress (16–21);
• High levels of distress (22–29); and
• Very high levels of distress (30–50).

Four ‘plus’ questions are used to assess functioning and how often the feelings were caused by physical health problems.

The Australian Bureau of Statistics (ABS) has several sources of long-term health conditions data which provide data to inform health policy and assist with health service planning.  For more information see 'Comparing ABS long-term health conditions data sources'.