This study sought to appraise internationally published literature investigating bullying in its association with deliberate self-harm (DSH). A systematic review and series of meta-analyses using random effects models were conducted. A total of 68 effect sizes, analyzing data from 156,284 adolescents aged 11-19 years were examined. Results showed significant associations between both traditional bullying perpetration (OR 1.81, 95% CI [1.33, 2.47], p < .0001) and victimization (OR 2.34, 95% CI [1.89, 2.89], p < .0001) and DSH. Cyber-bullying victimization (OR 3.55, 95% CI [2.71, 4.65], p < .0001) and the co-occurrence of traditional and cyber-bullying victimization (OR 3.39, 95% CI [1.56, 7.37], p = .002) were also associated with DSH. Moderator analyses showed variation in results based on methodological- and sample-level variables. Findings suggested that exposure to bullying, either as perpetrators or victims, poses risks for DSH.
Keywords: bullying perpetration; bullying victimization; cyber-bullying; deliberate self-harm; meta-analysis; traditional bullying.