This is a secondary data analysis of the National Health Survey (NHS) 2017-18 dataset (16). The NHS is an Australia-wide household-based health survey conducted at three-year intervals under the auspices of the Australian Bureau of Statistics (ABS). The NHS data is collected using a stratified multi-level sampling methodology to ensure all sections of the population living in private dwellings within the geographic scope of the survey are represented by the sample (excluding very remote and Indigenous Communities). The survey was implemented by trained ABS interviewers using Computer Assisted Personal Interviews. The survey collected a range of health-related information about Australians aged two years and above. Details regarding the survey are provided in the NHS Users’ Guide for 2017-18 (17).
Outcome measures
Self-assessed health was measured by one item asking “In general would you say that your health is excellent, very good, good, fair or poor?”
Psychological distress was measured by the 10-item Kessler Psychological Distress Scale (K10) (18). Respondents indicated how often they have experienced symptoms of anxiety and depression in the past four weeks (all of the time, most of the time, some of the time, a little of the time, none of the time). The K10 is scored from 10 to 50, with higher scores indicating higher levels of distress. Scores can be categorised as: low levels of distress (score 10–15); moderate levels of distress (16–21); high levels of distress (22–29); and very high levels of distress (30–50) (18).
Disability was based on whether the participant had a current condition that has lasted or was expected to last for six months or more, and if the condition had impacted their ability regarding movement and transport or their engagement in employment and education. The conditions assessed were shortness of breath, chronic or recurring pain, a nervous or emotional condition, or long-term effects as a result of a head injury, stroke or other brain damage. Participants were also asked about any other conditions they have that has lasted six months or more. Each participant was allocated to one of six categories of disability: profound (always need help with self-care, mobility and communication), severe (do not always but may require help at times), moderate (have difficulty with the self-care, mobility and communication), mild (simply required aids to undertake self-care, mobility and communication or are unable to do any of the additional mobility tasks [e.g. easily walk 200 metres]), school/employment restriction only (having a difficulty with school/study or work), or no disability.
Selected medical long-term conditions. Participants were asked if they have ever been told by a doctor or nurse that had any of the following long-term conditions (yes/no/don’t know): asthma, cancer, cardiovascular disease, arthritis, osteoporosis, diabetes, kidney diseases or mental, behavioural or cognitive conditions.
Other long-term medical conditions. Participants were also asked if they had any other conditions (not assessed as part of the selected medical conditions) that lasted or were expected to last for six months or more. The five most prevalent conditions across all housing types were listed.
Overweight/obese. Participant height (centimetres) and weight (kilograms) were measured and each participant’s body mass index (BMI) was calculated with a BMI score of ≥ 25kg/m2 classified as overweight or obese (19).
Health risk behaviours assessed were smoking, alcohol misuse, inadequate fruit and vegetable consumption, and inadequate physical activity. Current daily smokers were identified by asking “On average, on how many days do you smoke per week?”. Participants at risk of long-term harm (seven-day average drinking exceeded 2009 guidelines) (20) or short-term harm (consumed 5 or more alcoholic drinks on any one occasion) from alcohol misuse were identified. Survey participants were asked to report the number of serves of fruit and serves of vegetables they usually consumed each day and classified as having met or not met the 2013 NHMRC guidelines for fruit and vegetable consumptions separately (21). Physical activity was assessed by three survey items related to the number of times, minutes and intensity of physical activities over the last week. Participants met the 2014 Physical Activity Guidelines, Australia's Physical Activity and Sedentary Behaviour Guidelines for the participant’s age group (22).
Demographic characteristics included age, gender, employment status, education level, whether mainly spoke English at home and household composition (i.e., who the participant lives with).