Why and How to Promote Adolescents' Prosocial Behaviors: Direct, Mediated and Moderated Effects of the CEPIDEA School-Based Program.

Prosocial behaviors are considered integral to intervention goals that seek to promote successful youth development. This study examines the effect of a school-based intervention program entirely designed to promote prosocial behaviors called Promoting Prosocial and Emotional Skills to Counteract Externalizing Problems in Adolescence (Italian acronym CEPIDEA). The CEPIDEA curriculum was incorporated into routine educational practices and included five major components that reflect the personal determinants of prosocial behavior during adolescence. The present study assessed 151 students (48.7% female; M(age) = 12.4) of the intervention school and 140 students (51.2% female; M(age) = 13.0) of the control school at three points. A multi-group latent curve analysis revealed that the intervention group, compared with the control group, showed an increase in prosocial behavior, interpersonal self-efficacy beliefs, and agreeableness along with a decrease in physical aggression above and beyond the normative developmental trend of the these variables. Participants of the intervention also obtained higher grades than the control group at the end of middle school. Moderation effects for prosocial behavior and agreeableness evidenced that those who benefited most from the intervention were those adolescents with lower normative development of prosocial behavior, low initial level of agreeableness, and high initial level of physical aggression. The results also showed that the increase of prosocial behaviors mediated the decline of verbal aggression in adolescents who had attended the intervention. These findings suggest that interventions aimed at promoting prosocial behaviors while having the potential to support positive outcomes may also counteract or redirect negative trajectories of functioning.