Systematic Review and Individual Participant Data Meta-Analysis: Reducing Self-Harm in Adolescents: Pooled Treatment Effects, Study, Treatment, and Participant Moderators

Abstract

Objective: Self-harm is common in adolescents and a major public health concern. Evidence for effective interventions that stop repetition is lacking. This individual participant data (IPD) meta-analysis of randomized controlled trials (RCTs) aimed to provide robust estimates of therapeutic intervention effects and explore which treatments are best suited to different subgroups.

Method: Databases and trial registers to January 2022 were searched. RCTs compared therapeutic intervention to control, targeted adolescents ages 11 to 18 with a history of self-harm and receiving clinical care, and reported on outcomes related to self-harm or suicide attempt. Primary outcome was repetition of self-harm 12 months after randomization. Two-stage random-effects IPD meta-analyses were conducted overall and by intervention. Secondary analyses incorporated aggregate data from RCTs without IPD.

Results: The search identified 39 eligible studies; 26 provided IPD (3,448 participants), and 7 provided aggregate data (698 participants). There was no evidence that interventions were more or less effective than controls at preventing repeat self-harm by 12 months in IPD (odds ratio 1.06 [95% CI 0.86, 1.31], 20 studies, 2,949 participants) or IPD and aggregate data (odds ratio 1.02 [95% CI 0.82, 1.27], 22 studies, 3,117 participants) meta-analyses and no evidence of heterogeneity of treatment effects on study and treatment factors. Across all interventions, participants with multiple prior self-harm episodes showed evidence of improved treatment effect on self-harm repetition 6 to 12 months after randomization (odds ratio 0.33 [95% CI 0.12, 0.94], 9 studies, 1,771 participants).

Conclusion: This large-scale meta-analysis of RCTs provided no evidence that therapeutic intervention was more, or less, effective than control for reducing repeat self-harm. Evidence indicating more effective interventions in youth with 2 or more self-harm incidents was observed. Funders and researchers need to agree on a core set of outcome measures to include in subsequent studies.

Plain language summary: Self-harm is common in adolescents and linked to higher risks of repeated self-harm and suicide. This meta-analysis of 33 randomized controlled trials involving 4,146 adolescents found that therapeutic interventions were no more effective than standard care at preventing repeat self-harm at 12 months. However, interventions were more effective in youth with 2 or more self-harm incidents. The authors discuss limitations posed by the lack of uniform outcome measures for self-harm.

Clinical guidance: STUDY PREREGISTRATION INFORMATION: Reducing Self-harm in Adolescents: An Individual Participant Data Meta-analysis; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=152119.

Keywords: IPD meta-analysis; adolescents; self-harm; suicide; systematic review.