A meta-analysis of the effect of school-based anti-bullying programs.

Bullying is a serious public health problem, and many studies have examined the effect of school-based anti-bullying programs. However, these programs and those outcomes are complex, broad, and diverse. Research is needed into the optimal strategies for these comprehensive programs, which consider both the effectiveness and cost of programs. We performed a meta-analysis of 13 studies using the Comprehensive Meta-Analysis software package to calculate effect size (ES) and the Q statistic. We conducted subgroup analyses to examine the differences based on student grade level, program duration, and program strategy. The pooled ES calculation indicated that school-based anti-bullying programs have a small to moderate effect on victimization. The results of the Q test indicated significant heterogeneity across studies of victimization (Q = 39.625; I (2) = 69.7%; p < .001). Studies involving training in emotional control (p < .01), peer counseling (p < .05), or the establishment of a school policy on bullying (p < .05) showed significantly larger ESs on victimization than did studies that did not involve these strategies. Effective school-based anti-bullying programs should include training in emotional control, peer counseling, and the establishment of a school policy on bullying.