Background: Psychosis is a significant, yet understudied, risk factor for suicide. There has yet to be a systematic investigation examining the rate and predictors of inclusion of psychotic disorders or symptoms in suicide-focused trials. Aim: Our aim was to conduct a systematic review of inclusion/exclusion of psychosis in studies with suicidal ideation or behavior as a primary endpoint, rate of inclusion across intervention type and other characteristics, and criteria used to exclude psychosis and accompanying rationale. Method: A literature search was conducted using PubMed, Cochrane Library, and PsycInfo to identify relevant articles published between 2000 and 2018. Statements regarding inclusion/exclusion were codified by authors. Results: Out of 122 studies selected, 75 (61.5%) excluded individuals with psychosis. This rate varied by intervention and sample size, but not by year of study or country of origin. Only 9% provided a rationale for psychosis exclusion. Limitations: Minimal reporting of participants' diagnosis in studies disallowed analysis of the rate of inclusion of psychosis in samples. Conclusion: Three out of five trials with suicide-related primary outcomes excluded psychosis; thus, people with psychosis are poorly represented in suicide-specific studies. This disparity could be remedied by either adapting protocols to include people with psychosis or developing new, tailored treatments.
Keywords: clinical trial; intervention; psychosis; suicide.