The role of bystanders in bullying and cyberbullying prevention is crucial. Strategies must be tailored to address the shared and unique factors in online and offline contexts, ensuring that interventions create an environment where bystanders are empowered and feel responsible to act against bullying and cyberbullying. This meta-analysis examines and compares the effectiveness of interventions in enhancing bystander behaviors in bullying and cyberbullying scenarios. A comprehensive search was conducted using databases including PsycINFO, Medline, Sociological Abstracts, Social Service Abstracts, ERIC, and Scopus. Quasi-experimental and randomized controlled trials published before March 31, 2024 that reported that the effects of bystander interventions were included. The synthesis comprised 49 studies, reporting an overall random effect size (Cohen's d) of 0.25. The results highlight the crucial roles of enhancing knowledge, self-efficacy, and coping skills. Subgroup analysis revealed that the effective bystander interventions include smaller sample sizes (<100 participants), shorter durations (<1 month), targeting college students, and utilizing offline intervention approaches and digital techniques. These findings emphasize the promising effects and tailored characteristics of bystander intervention programs in bullying and cyberbullying contexts. Our review identifies avenues for future research within educational settings to develop more effective bystander behavior interventions to reduce bullying and cyberbullying.
Keywords: bullying; bystander; cyberbullying; effectiveness; intervention; meta-analysis.