Known unknowns and unknown unknowns in suicide risk assessment: evidence from meta-analyses of aleatory and epistemic uncertainty.

Suicide risk assessment aims to reduce uncertainty in order to focus treatment and supervision on those who are judged to be more likely to die by suicide. In this article we consider recent meta-analytic research that highlights the difference between uncertainty about suicide due to chance factors (aleatory uncertainty) and uncertainty that results from lack of knowledge (epistemic uncertainty). We conclude that much of the uncertainty about suicide is aleatory rather than epistemic, and discuss the implications for clinicians.

Australia's economic transition, unemployment, suicide and mental health needs.

OBJECTIVE: There have been substantial changes in workforce and employment patterns in Australia over the past 50 years as a result of economic globalisation. This has resulted in substantial reduction in employment in the manufacturing industry often with large-scale job losses in concentrated sectors and communities. Large-scale job loss events receive significant community attention. To what extent these mass unemployment events contribute to increased psychological distress, mental illness and suicide in affected individuals warrants further consideration. METHODS: Here we undertake a narrative review of published job loss literature. We discuss the impact that large-scale job loss events in the manufacturing sector may have on population mental health, with particular reference to contemporary trends in the Australian economy. We also provide a commentary on the expected outcomes of future job loss events in this context and the implications for Australian public mental health care services. RESULTS AND CONCLUSION: Job loss due to plant closure results in a doubling of psychological distress that peaks 9 months following the unemployment event. The link between job loss and increased rates of mental illness and suicide is less clear. The threat of impending job loss and the social context in which job loss occurs has a significant bearing on psychological outcomes. The implications for Australian public mental health services are discussed.

Meta-Analysis of Longitudinal Cohort Studies of Suicide Risk Assessment among Psychiatric Patients: Heterogeneity in Results and Lack of Improvement over Time.

OBJECTIVE: It is widely assumed that the clinical care of psychiatric patients can be guided by estimates of suicide risk and by using patient characteristics to define a group of high-risk patients. However, the statistical strength and reliability of suicide risk categorization is unknown. Our objective was to investigate the odds of suicide in high-risk compared to lower-risk categories and the suicide rates in high-risk and lower-risk groups. METHOD: We located longitudinal cohort studies where psychiatric patients or people who had made suicide attempts were stratified into high-risk and lower-risk groups for suicide with suicide mortality as the outcome by searching for peer reviewed publications indexed in PubMed or PsychINFO. Electronic searches were supplemented by hand searching of included studies and relevant review articles. Two authors independently extracted data regarding effect size, study population and study design from 53 samples of risk-assessed patients reported in 37 studies. RESULTS: The pooled odds of suicide among high-risk patients compared to lower-risk patients calculated by random effects meta-analysis was of 4.84 (95% Confidence Interval (CI) 3.79-6.20). Between-study heterogeneity was very high (I2 = 93.3). There was no evidence that more recent studies had greater statistical strength than older studies. Over an average follow up period of 63 months the proportion of suicides among the high-risk patients was 5.5% and was 0.9% among lower-risk patients. The meta-analytically derived sensitivity and specificity of a high-risk categorization were 56% and 79% respectively. There was evidence of publication bias in favour of studies that inflated the pooled odds of suicide in high-risk patients. CONCLUSIONS: The strength of suicide risk categorizations based on the presence of multiple risk factors does not greatly exceed the association between individual suicide risk factors and suicide. A statistically strong and reliable method to usefully distinguish patients with a high-risk of suicide remains elusive.