Trajectories of prosocial behavior from adolescence to early adulthood: associations with personality change.

The goal of this study was to identify heterogenic longitudinal patterns of change in prosocial behavior from adolescence to early adulthood and their association with change in Big Five Factor (BFF) personality traits from adolescence until early adulthood. Participants were 573 Italian adolescents aged approximately 13 at the first assessment and 21 at the last assessment. Using growth mixture modeling, low increasing (LI; 18%), medium quadratic (MQ; 26%), and high quadratic (HQ; 54%) trajectories of prosocial behavior were distinguished. Generally, the LI trajectory group predicted an increase in Conscientiousness over time, whereas the HQ trajectory group predicted greater change in Agreeableness and Openness. In addition, positive changes in Conscientiousness, Agreeableness, and Openness between ages 13 and 21 predicted a higher probability of belonging to the HQ prosocial group. Findings support a malleable perspective on personality and identify longterm positive pathways for youths' prosocial development.