National Study of Mental Health and Wellbeing: Follow up Study

The 2020–2022 National Study of Mental Health and Wellbeing (NSMHW) was conducted by the Australian Bureau of Statistics (ABS) between December 2020 and October 2022 and provides prevalence estimates of mental disorders among Australians aged 16-85 years.

All participants of the NSMHW were asked if they would be willing to be contacted for a follow up survey. Of those who consented, a subset were contacted on average, 12 months after the completion of the NSMHW. These people were asked to complete the Health and Wellbeing Follow up Survey (HWFUS).

The aim of the HWFUS was to provide a longitudinal perspective on whether people use health services for their mental health and the impact, or otherwise, of the use of services on mental health.

Data from the HWFUS is disseminated as the Follow up Study.

For further information about the NSMHW see National Study of Mental Health and Wellbeing Methodology.

People who were asked to complete the Follow up Study were aged over 18 years and met at least one of the following criteria based on their responses to the NSMHW:

• Had a lifetime disorder with 12-month symptoms
• Had a lifetime disorder but no 12-month symptoms
• Had no lifetime disorder with 12-month symptoms
• Reported suicidal thoughts or behaviours
• Reported self-harm
• Reported disordered eating behaviours
• Had a consultation with a health professional for mental health in the 12 months prior to interview
• Were hospitalised for mental health problems in the 12 months prior to interview.

The NSMHW asked respondents about their experiences and symptoms of mental ill-health throughout their life. Their responses to the questionnaire were then classified using the International Classification of Diseases - Tenth Revision (ICD-10) and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) to produce population estimates of the prevalence of mental health disorders among Australians aged 16-85 years. The term mental disorder is used in this publication to align with these definitions and criteria.

People who were classified as having a ‘lifetime disorder with 12-month symptoms’ met the diagnostic criteria for a mental disorder at some time in their life and had sufficient symptoms of that disorder in the 12 months prior to their NSMHW interview.

People who were classified as having a ‘lifetime disorder with no 12-month symptoms’ met the diagnostic criteria for a mental disorder at some time in their life. This does not imply that these people had a mental disorder throughout their entire life.

People who were classified as having ‘no lifetime disorder with 12-month symptoms’ did not meet the diagnostic criteria for having a mental disorder at any time in their life but reported symptoms of a disorder in the 12 months prior to their NSMHW interview.

People who had a ‘lifetime disorder with 12-month symptoms’, had a ‘lifetime disorder but no 12-month symptoms’ or had ‘no lifetime disorder with 12-month symptoms’ for the following disorders were in scope for the Follow up Study: 

• DSM-IV Substance Use Disorder (includes Alcohol Abuse, Alcohol Dependence, Drug Abuse (includes Cannabis Abuse, Stimulant Abuse, Sedative Abuse, Opioid Abuse) and Drug Dependence (includes Cannabis Dependence, Stimulant Dependence, Sedative Dependence, Opioid Dependence))
• ICD-10 Substance Use Disorder (includes Alcohol Harmful Use, Alcohol Dependence, Drug Harmful Use (includes Cannabis Harmful Use, Stimulant Harmful Use, Sedative Harmful Use, Opioid Harmful Use) and Drug Dependence (includes Cannabis Dependence, Stimulant Dependence, Sedative Dependence, Opioid Dependence))
• DSM-IV Dysthymia
• ICD-10 Dysthymia
• DSM-IV Minor Depressive Disorder
• ICD-10 Minor Depressive Episode
• DSM-IV Major Depressive Disorder
• ICD-10 Moderate Depressive Episode
• DSM-IV Major Depressive Episode
• ICD-10 Major Depressive Episode
• DSM-IV Obsessive Compulsive Disorder
• ICD-10 Obsessive Compulsive Disorder
• DSM-IV Panic Attack
• ICD-10 Panic Attack
• DSM-IV Panic Disorder
• ICD-10 Panic Disorder
• DSM-IV Generalised Anxiety (includes Generalised Anxiety Disorder (12 months) 1mth duration and Generalised Anxiety Disorder (12 months) 3mth duration
• ICD-10 Generalised Anxiety
• DSM-IV Social Phobia
• ICD-10 Social Phobia
• DSM-IV Post Traumatic Stress Disorder
• ICD-10 Post Traumatic Stress Disorder
• DSM-IV Agoraphobia with or without Panic Disorder
• DSM-IV Agoraphobia without Panic Disorder
• ICD-10 Agoraphobia with/without Panic Disorder
• ICD-10 Bipolar Affective Disorder
• DSM-IV Bipolar Affective Disorder (includes Bipolar I and Bipolar II Disorder)
• DSM-IV Bipolar Subthreshold Disorder
• DSM-IV Hypomania
• ICD-10 Hypomania
• DSM-IV Sub Hypomania
• DSM-IV Mania
• ICD-10 Mania.

The ‘without hierarchy’ versions of the ICD-10 and DSM-IV classifications were used.

At the time of completing the NSMHW, respondents were told that the ABS may conduct future surveys to aid in understanding Australia’s health. Those who agreed to participate in a follow up survey were asked to provide their contact details. These contact details were used to invite respondents to participate in the Follow up Study. To minimise bias in the results, the detailed criteria for the Follow up Study were not shared with respondents. 

Respondents had the option to self-complete the survey online or with an ABS interviewer over the phone. 

As the NSMHW was collected from two cohorts, the Follow up Study was also collected from two cohorts. Cohort 1 was collected between April 2022 and November 2022. Cohort 2 was collected between April 2023 and September 2023. Participation was voluntary.

The ABS thanks all participants for their involvement in the Health and Wellbeing Follow up Survey. The information collected is critical to mental health policy, program development and evaluation in Australia. 

Of those that participated in the NSMHW, 9,199 people met the scope criteria for the Follow up Study. 3,079 people, or 33.5%, of the in-scope sample completed the Follow up Study. 

Most of the Follow up Study content comprised a reduced set of questions from the NSMHW, including:

• Education, employment, and financial stress
• Self-assessed health and mental health status, psychological distress, and functioning
• Suicidality
• Self-harm
• Use of health services for mental health
• Social connections
• Strategies used for mental wellbeing.

As was done for the NSMHW, Pharmaceutical Benefits Scheme (PBS) mental health-related medications data was sourced from the PBS instead of being collected directly from survey respondents.

More detailed information about the content collected in both the NSMHW and the Follow up Study is available in the National Study of Mental Health and Wellbeing Methodology.

See the Data Item List for full details of the content collected for the Follow up Study.

Unlike the NSMHW, the Follow Up Study was not designed to provide nationally representative estimates for the Australian population aged 16-85 years. Data collected from the Follow up Study have not been weighted and represent only those people who participated. Care should be taken when generalising the results to the broader population. 

This release presents selected results from the Follow up Study.

Detailed microdata is available on DataLab for users who want to undertake complex analysis of the microdata in the secure ABS environment. A data item list is available.

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.

Some techniques used to guard against identification or disclosure of confidential information in statistical output are suppression of sensitive data, random adjustments to very small values, and aggregation of data. To protect confidentiality within this publication, some data have been aggregated.

The NSMHW interview measured the prevalence of mental disorders among Australians aged 16–85 years using the World Health Organization Composite International Diagnostic Interview (CIDI 3.0). Respondents were asked about their experiences and symptoms of mental ill-health throughout their lifetime, from which two key measures were analysed:

• Lifetime mental disorders, which refers to the number of people who met the diagnostic criteria for having a mental disorder at some time in their life. This does not imply that a person has had a mental disorder throughout their entire life
• 12-month mental disorders, which refers to the number of people who met the diagnostic criteria for having a mental disorder at some time in their life and had sufficient symptoms of that disorder in the 12 months prior to when they completed their NSMHW interview. The term ‘had a 12-month mental disorder’ refers to people in this group. 

In the NSMHW, three groups of mental disorders were assessed ­– Anxiety, Affective and Substance Use disorders ­– based on definitions and criteria of the World Health Organization International Classification of Diseases, Tenth Revision (ICD-10) and the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Results in this article are based on the ICD-10 classifications, and the term 'mental disorder' is used to align with these definitions and criteria.

See the NSMHW Methodology for more information.

Type of health professional seen for mental health includes:

• General practitioner
• Psychiatrist
• Psychologist
• Mental health nurse
• Other mental health professional, including social worker, counsellor, occupational therapist
• Hospital admissions for mental health.

Services include:

• Crisis support or counselling services
• Online treatment programs, training, assessments or other tools to improve mental health
• Mental health support groups, forums or chat rooms
• Information about mental illness, treatment options or services.

Medications data was sourced from the Pharmaceutical Benefits Scheme (PBS). Data relates to mental health-related medications dispensed to the respondent in the 12 months prior to the respective survey, and not how or if they were used. While these medications are commonly prescribed for treating mental health conditions, they may also be prescribed to treat other conditions.

PBS medication types are classified using the 2023 Anatomical Therapeutic Chemical (ATC) classification system which is maintained by the World Health Organization (WHO) and widely used internationally.

Mental health-related medications included in NSMHW and Follow up Study data are:

• Antipsychotics (N05A)
• Anxiolytics (N05B)
• Hypnotics and sedatives (N05C)
• Antidepressants (N06A)
• Psychostimulants, agents used for ADHD and nootropics (N06B).