Trajectories of adolescents' adjustment behaviors across the transition to upper secondary education: The role of individual and environmental factors

This longitudinal study examined the developmental trajectories of 901 Finnish adolescents' (M = 15.3 at T1, SD = 0.37) adjustment behaviors (prosocial behavior and externalizing problems) across the transition to upper secondary education. The role of adolescents' temperament and relationship with parents and teachers were investigated. Four trajectories of adjustment behaviors were distinguished: moderate prosocial and high externalizing (25.8 %), high prosocial and low externalizing (64.9 %), decreasing prosocial and increasing externalizing before the transition (7.4 %), decreasing prosocial and increasing externalizing after the transition (1.9 %). Adolescents' higher negative affectivity, lower effortful control, and less close and conflicting relationship with parents and teachers are positively associated with the trajectory of moderate prosocial behavior and high externalizing problems. In contrast, high effortful control, high closeness, and low conflict are positively associated with the trajectories of high prosocial and low externalizing problems as well as decreasing prosocial and increasing externalizing after the transition.