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Key facts about mental illness

1 in 5 adult Australians will experience a mental illness in any given year. A mental illness diagnosis is made by a qualified healthcare professional (such as a doctor or other mental health professional) according to a standardised criterion.

Two common standardised manuals that set out these criteria are:

  • the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5)
  • International Classification of Diseases, 10th Revision (ICD-10) (This is the standardised manual used by Queensland Health mental health services).

Anxiety is the most common mental health condition in Australia. Over a 12 month period, over 2 million Australians will experience anxiety (beyondblue, 2019).

Between March 2018-2019, parental mental health difficulties were noted for 53% of families in Queensland where harm or risk of harm was substantiated by Child Safety (Department of Child Safety, Youth and Women, 2019).

Almost half (45%) of Australians aged between 16 and 85 will be affected by a mental illness at some point in their lives (Blackdog institute, n.d.). Some groups who are at higher risk of mental illness include:

  • children and young people in out of home care
  • culturally and linguistically diverse (CALD) groups
  • Aboriginal and Torres Strait Islander peoples
  • adult survivors of sexual and other abuse
  • people in regional, rural or remote areas
  • those involved with the criminal justice system.

(NSW Mental Health Commission, 2017).

National Survey of Mental Health

Australia undertakes a program of surveys called the National Survey of Mental Health and Wellbeing. These surveys provide evidence on the prevalence of mental health disorders in Australia. Key findings include:

  • Survey of the adult population aged 16 – 85 (conducted most recently in 2007). This survey found that around 7.3 million (45%) of Australians aged 16–85 will experience a high prevalence mental disorder, such as depression, anxiety or a substance use disorder in their lifetime. 1 in 5 experienced a mental disorder over a 12 month period.
  • Survey of children and adolescents aged 4 – 17 (conducted most recently in 2013-14). Analysis from the survey estimates almost 1 in 7 (13.9%) of children and adolescents were assessed as having a mental illness.
  • Survey of people living with psychotic illness aged 16 – 84 (conducted most recently in 2010). Almost 64,000 people had a psychotic illness (0.5% of the population) were in contact with public specialised mental health services each year.

Further information about mental illness

Follow the below links to find out more about some common mental illnesses:


Practice prompt

Mental health issues are common, though at times poorly understood.  Refer to Resources and support on the the Black Dog Institute website for more information.  

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