A systematic review: Identifying the prevalence rates of psychiatric disorder in Australia's Indigenous populations

Objective: This review aimed to draw on published literature to identify the prevalence rates of psychiatric disorders in Australia's Indigenous populations, Aboriginal and Torres Strait Islander peoples.

Method: A systematic review following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) model was conducted using the following electronic databases: PubMed, Scopus, Web of Science, MEDLINE, PsycINFO, PsycARTICLES, and Informit Indigenous and Health Collections. Studies were included for analysis if they were empirical quantitative studies reporting prevalence rates for any psychiatric disorder in Indigenous people.

Results: Of the 1584 papers extracted by the search strategy, 17 articles met the eligibility criteria and were reviewed in detail. Methodology, sampling strategy and study design varied greatly across these 17 studies. Prevalence rates varied by disorder and are as follows: major depressive disorder (4.3-51%); mood disorders (7.7-43.1%); post-traumatic stress disorder (14.2-55.2%); anxiety disorders (17.2-58.6%); substance dependence (5.9%-66.2%); alcohol dependence (21.4-55.4%); and psychotic disorders (1.68-25%). While the number of studies on community-based Indigenous populations was limited, available evidence suggested that prevalence rates are higher in prison populations compared with community-based studies.

Conclusions: It was identified that there is limited evidence on the occurrence of psychiatric disorders for Indigenous people in the general community. More research in this area is essential to provide accurate and reliable estimates and to provide a baseline for evaluating the effectiveness of programs aimed at reducing the high mental health burden experienced by Indigenous Australians. Future research needs to ensure that standardised and validated methods are used to accurately estimate the prevalence of psychiatric disorders among Indigenous Australians.