Estimating levels of mental health service need by small geographic area: A case study for Aboriginal and Torres Strait Islander adults living in South East Queensland

Objective: The objective of this study was to determine regional variation in need for mental health care for Aboriginal and Torres Strait Islander adults (18+ years). Methods: Three Australian Indigenous health surveys were analysed, and prevalence rates of high/very high psychological distress (as per the Kessler-5 tool) by the Index of Relative Socio-economic Disadvantage were computed and combined via meta-analysis. These estimates were applied to census population data to estimate regional needs and summed to geographic planning regions. Final estimates were assessed for face validity by comparing with other existing estimates of mental health need. Results: The Index of Relative Socioeconomic Disadvantage had a dose-response relationship with high/very high psychological distress, whereby the more disadvantaged an area, the greater the levels of reported distress. This methodology resulted in varying levels of need within South East Queensland. Conclusions: The approach was found to have good face validity and provides a data-driven method to determine relative levels of need. Implications for Public Health: To ensure equity of mental health service provision, planners should account for variation in levels of need within a catchment. This method may be used throughout Australia to determine regional variation in need for care where other data are lacking to ensure evidence-based investment planning decisions at the local level.