Defining and measuring psychosocial disability in Australia: Assessment of national surveys and administrative datasets

OBJECTIVE: We aimed to assess the alignment in defining and measuring psychosocial disability and/or mental health challenges across major Australian national mental health data sources. METHODS: We reviewed the definition and measurement of psychosocial disability and mental health challenges in two stages. First, we examined the data items across five national data sources: the Survey of Disability, Ageing and Carers (SDAC), the National Health Survey (NHS), the National Study of Mental Health and Wellbeing (NSMHW), the Census and the National Disability Insurance Scheme (NDIS) administrative data. In the second stage, we analysed the prevalence of psychosocial disability and mental health challenges across the datasets. RESULTS: The definition and measurement approaches for psychosocial disability and mental health challenges vary across data sources, reflecting differences in the conditions included and the purpose for which data were collected. Psychosocial disability is inconsistently defined: broad population surveys (SDAC, NHS) include neurodevelopmental and neurodegenerative conditions, whereas the NDIS captures only severe mental illnesses with substantial functional impairment. Prevalence across Australia varied widely from 42.9% for lifetime mental disorders (NSMHW) and 26.1% for long-term conditions (NHS), down to 6% when strictly defining psychosocial disability (SDAC). CONCLUSIONS: There are variations in definitions and measurement across major Australian mental health data sources with respect to conditions captured in the datasets and the definitions used. Researchers and policymakers should therefore critically appraise - and where possible adjust for - these variations when using these data to inform strategic decisions and resource allocation.