Abstract: Eight studies met inclusion criteria. They were heterogeneous in terms of participants, study designs, and interventions. Five of eight studies had high risk of bias. In 3 RCTs (312 participants), classroom-based didactic and experiential programs increased short-term knowledge of suicide (SMD = 1.51, 95% CI 0.57 to 2.45; moderate quality evidence) and knowledge of suicide prevention (SMD = 0.72, 95% CI 0.36 to 1.07; moderate quality evidence). The effect on suicide prevention self-efficacy in one RCT (152 participants) was uncertain (SMD = 0.20, 95% CI -0.13 to 0.54; low quality evidence). One CBA analysed the effects of an institutional policy that restricted student access to laboratory cyanide and mandated professional assessment for suicidal students. The incidence of student suicide decreased significantly at one university with the policy relative to 11 control universities, 2.00 vs. 8.68 per 100,000 (Z = 5.90; P < 0.05). Four CBAs explored effects of training 'gatekeepers' to recognize and respond to warning signs of emotional crises and suicide risk in students they encountered. The magnitude of effect sizes varied between studies. Gatekeeper training enhanced short-term suicide knowledge in students, peer advisors residing in student accommodation, and faculty and staff, and suicide prevention self-efficacy among peer advisors. There was no evidence of an effect on participants' suicide-related attitudes or behaviors. One CBA found no evidence of effects of gatekeeper training of peer advisors on suicide-related knowledge, self-efficacy, or gatekeeper behaviors measured four to six months after intervention. We found insufficient evidence to support widespread implementation of any programs or policies for primary suicide prevention in post-secondary educational settings. As all evaluated interventions combined primary and secondary prevention components, we were unable to determine the independent effects of primary preventive interventions. Classroom instruction and gatekeeper training increased short-term suicide-related knowledge. We found no studies that tested the effects of classroom instruction on suicidal behavior or long-term outcomes. Limited evidence suggested minimal longer-term effects of gatekeeper training on suicide-related knowledge, while no evidence was found evaluating its effect on suicidal behavior. A policy-based suicide intervention reduced student suicide, but findings have not been replicated. Our findings are limited by the overall low quality of the evidence and the lack of studies from middle- and low-income countries. Rigorously designed studies should test the effects of preventive interventions on important health outcomes, including suicidal ideation and behavior, in varying post-secondary settings.

Plain-language summary: We identified eight studies that were eligible for this Cochrane Review. All studies had both primary and secondary prevention components. That is, they targeted students known to be suicidal as well as those not known to be suicidal. We separately analysed the effects of classroom instruction, institutional policies, and gatekeeper training programs. Gatekeeper training programs train people to recognize and respond to warning signs of emotional crises or suicide risk in students they encounter. The evidence is current to June 2011. Three studies, including 312 students, evaluated classroom instruction. Classroom instruction increases short-term knowledge of suicide and suicide prevention. It may slightly enhance short-term confidence in ability to prevent suicide. However, long-term effects have not been studied. Effects of classroom instruction on suicidal behavior have also not been studied. One study evaluated an institutional policy. The policy restricted access to laboratory cyanide and required professional assessment for students who threatened or attempted suicide. The policy significantly reduced student suicides. These findings have not been tested in other post-secondary institutions. Four studies, ranging from 53 to 146 participants, evaluated the effect of gatekeeper training programs. Gatekeeper training may lead to small-to-medium improvements in short-term suicide-related knowledge and confidence about being able to prevent suicide. We found no evidence that gatekeeper training improved short-term attitudes toward suicide or long-term knowledge or behaviors about suicide. The effect of gatekeeper training on suicide or suicidal behavior has not been evaluated. The quality of evidence for short-term knowledge of suicide and suicide prevention was moderate. For suicide prevention self-efficacy, the quality of evidence was low. The quality of evidence was reduced because results were not similar across studies and there were not enough data.