The theory of reasoned action (ToRA) has been proposed as a framework for cyberbullying prevention design, targeting attitudes and norms. In this study effects of a long (10 weekly sessions) and a short (one day, four sessions) cyberbullying prevention program based on the ToRA were compared with a control group over 9 months. Longitudinal data from 722 students (mean age = 13.36) on cyberbullying, somatic symptoms, attitudes, and norms were analyzed within a structural equation model. Participation in the long intervention group significantly reduced cyberbullying (d = -0.584) and somatic symptoms (d = -0.316). No between-group differences emerged for attitudes and norms. Developmental trajectories and associations were found to be as suggested by ToRA in both cross-sectional and change-score analyses.
© 2018 Society for Research on Adolescence.