It is official, they are different: Discrepancies between national statistical agency and register-based state suicide mortality statistics in Australia

Background: In Australia, most state-based suicide registers now publicly release suicide mortality data alongside those the Australian Bureau of Statistics (ABS) releases annually. Aims: This study compared ABS’s recorded suicides with three state-based suicide registers (Queensland, Victoria, and Tasmania). We compared their case definitions and coding approaches to assist users in choosing the most suitable data source and interpret differences between sources. Method: We collated the number of suicides by year of registration and occurrence (2006–2020). We compared the scope and coding of suicides between ABS and the registers using publicly available suicide reports and data releases. Results: The ABS’s annual suicide numbers are similar to (and in Tasmania exceed) the numbers reported by state-based registers. The ABS year of occurrence data diverges substantially from the Victoria and Queensland register data in 2020, perhaps attributable to ongoing ABS revision processes. Minimal overlap exists between the case definitions and coding practices of the ABS and registers. Limitations: This is not an individual-level concordance study. Conclusion: Despite different case definitions and coding practices, the two sources produced largely consistent data. They have complementary strengths: timeliness (suicide register data) and enabling cross-jurisdictional comparisons (ABS data).