Supplementary Material for: Effectiveness of psychotherapy on prevention of suicidal reattempts in psychiatric emergencies: A systematic review and network meta-analysis of randomized controlled trials

Introduction: Many psychological interventions aim to prevent suicide, but there is limited information regarding their comparative effectiveness. Objectives: We conducted a systematic review and network meta-analysis to evaluate the relative effects of psychological interventions for preventing suicide re-attempts in psychiatric emergencies. Methods: We searched PubMed, Embase, Cochrane, and PsycINFO from inception to December-1-2022. Selection and data extraction were conducted independently by two reviewers based on pre-specified criteria. We evaluated the efficacy of interventions, potential effect moderators, and study quality both within individual studies and across studies. Global and local inconsistencies and publication bias were explored. The primary outcome was suicide re-attempt rate. The network meta-analysis was conducted using the “netmeta” package in R. The protocol was registered with PROSPERO(CRD42021291407). Results: Of 3,155 participants from 26 RCTs included in the network meta-analysis. Cognitive–behavioral therapy(CBT) was the only intervention that was more effective than a common comparator for reducing suicide re-attempts among psychological interventions in both direct and indirect comparisons (OR[95%CI], 0.46[0.25–0.85]vs.0.47[0.27-0.83]). CBT had the highest score(P-score=0.8727) across the various psychological interventions. Neither global nor local inconsistency was significant. There was no clear evidence of violations of the transitivity assumption when comparing characteristics of studies across interventions. Publication bias was not suspected for the primary outcome. Conclusions: CBT may be regarded as a reasonable first-line psychological intervention to prevent re-attempts among people with previous suicide attempts. We observed a moderate quality of evidence supporting an 87% probability of CBT being the best treatment available for preventing suicide re-attempts.