Abstract This 2-year longitudinal study investigated the role of peer group leaders' prosociality and aggression in social, school, and psychological adjustment among early adolescents. Participants included 2,155 middle school students (1,085 boys; initial Mage = 12.91 years) in China. Data were collected in 2019 and 2021 from multiple sources, including self-reports, peer nominations, teacher ratings, and school records. Peer groups and their leaders were identified using the WalkTrap community detection algorithm, resulting in 239 peer group leaders across 220 peer groups. Multilevel analyses showed that group leaders' prosociality was positively associated with members' later prosociality and social preference. Group leaders' aggression was positively associated with members' aggression and behavioral and learning problems. The results indicate the importance of group leaders' characteristics for adolescent development.
Zhou et al. (Thu,) studied this question.