A Meta-Analysis of Bullying Victimization and Adolescent Self-Harm and Suicidal Outcomes Across Effect-Size Metrics.

Bullying victimization is associated with adolescent self-harm and suicidal outcomes, yet substantial heterogeneity remains in the magnitude and pattern of these associations. One challenge in interpreting this heterogeneity is that studies characterize bullying-related associations using effect-size metrics that represent risk in different statistical forms. Odds ratios (ORs) estimate differences in the likelihood of defined outcomes, whereas correlation coefficients (r) quantify associations across measured variation. This meta-analysis therefore synthesized OR- and correlation-based evidence separately to examine whether patterns of association and heterogeneity vary across statistical representations. The analysis included 120 studies comprising 622,571 participants from China, Europe, and North America. Among samples reporting demographic information, the sample-size-weighted mean age was 14.7 years, and 50.3% of participants were female. Bullying victimization was significantly associated with self-harm and suicidal outcomes across both frameworks. However, different patterns of moderation emerged across metrics and outcomes: bullying type and measurement approach moderated OR-based associations for both self-harm and suicidal outcomes, whereas study design moderated only correlation-based self-harm associations. Cultural region additionally moderated OR-based suicidal outcomes. These findings suggest that ORs and correlations provide complementary rather than interchangeable perspectives on bullying-related risk because conclusions about its variability may depend partly on how associations are statistically represented. Considering both frameworks may therefore provide a more differentiated understanding of bullying-related risk during adolescence.