Background Following a suicide attempt, only a third of people receive outpatient treatment, highlighting the need for low-threshold brief interventions and contacts (BICs). We aimed to examine the effectiveness of BICs.Methods In this systematic review and meta-analysis, we searched MEDLINE, Embase, Cochrane CENTRAL, PsycInfo, Web of Science, and ProQuest, and gray literature from inception to June 18, 2025, for randomized controlled trials of BIC in adults following a suicide attempt. Studies were included if they investigated the effectiveness of BICs compared with control for adults (aged 18-65) after a suicide attempt, intended to reduce suicide re-attempts, suicidal ideation, self-harm, non-suicidal self-injury, or linkage to mental health (MH) services. The main outcomes included suicide re-attempts, self-harm, suicidal ideation, non-suicidal self-injury (NSSI), and linkage to MH services. We extracted raw frequency counts and means/SDs for use in random-effects meta-analyses of odds ratios and standardized mean differences, respectively. Quality of the evidence was assessed with RoB 2 and GRADE. This study is registered with PROSPERO, CRD42022271143.Findings Thirty-six trials (9552 participants; 1993-2025) were included, with 33 trials eligible for meta-analysis. Suicide re-attempts were significantly reduced after BICs compared with control (moderate-certainty evidence; OR = 0.72, 95% CI 0.54, 0.95; I2 = 56.8%; n = 23 studies). Reductions in suicidal ideations were observed after BICs compared with control (low-certainty evidence; SMD = -0.20, 95% CI -0.36, -0.05; I2 = 63.4%; n = 15 studies). We found no evidence for reductions in self-harm recurrence (very low-certainty evidence; OR = 0.66, 95% CI 0.22, 1.97; I2 = 80.9%; n = 4 studies) and increases in linkage to MH services (very low-certainty evidence; OR = 2.25, 95% CI 0.71, 7.17; I2 = 89.8%; n = 6 studies). There were too few studies for an investigation of NSSI. Most trials showed some concerns (22 studies, 61%), while fewer showed high risk of bias (7 studies, 19%). Risk of bias, heterogeneity, and imprecision contributed to the downgrading of certainty.Interpretation Our findings have important implications for clinical practice and suicide prevention. Even when delivered in a single session, BICs can effectively reduce the recurrence of suicide attempts and may also decrease suicidal thoughts. Although conclusions for self-harm recurrence and linkage to MH services were limited, these interventions can be considered a practical and potentially essential element of suicide prevention strategies. Further high-quality trials are needed to confirm effects across additional outcomes and populations.Funding The study was supported by funding from the Swiss National Science Foundation (501100001711-205913); the EMDO Foundation of the University of Zurich; the HOLCIM enterprise for the Promotion of Scientific Further Education.
Homan et al. (Sun,) studied this question.