Positive affect and hope contribute to individuals’ psychological adjustment and positive youth development. The purpose of the study was to examine growth in positive and negative affect as well as state hope in Chinese adolescents in a juvenile correctional institution. We also investigated whether distinct trajectories of affect and hope predicted mental health and externalizing, internalizing, and prosocial behavior. The study included 198 male adolescents in a Chinese juvenile correctional institution and comprised nine measurement points (T1-T9) which were one week apart, respectively. Positive and negative affect and state hope were assessed from T1 to T8, and mental health and internalizing, externalizing, and prosocial behavior were measured at T9. Analyses of latent growth curve and latent class growth models were estimated. It was found that positive and negative affect, as well as state hope, decreased over time. Youth in classes characterized by higher state hope and lower negative affect reported better mental health than youth in classes characterized by lower levels of these constructs. Because of the beneficial effects of lower negative affect and higher state hope on mental health and internalizing, externalizing, and prosocial behavior, interventions strengthening hope and reducing negative affect may promote positive youth development in juvenile correctional institutions.
