Peer stress and adolescent deviant behaviors: Unraveling the roles of loneliness and stress mindset.

Peer stress during adolescence is a salient interpersonal challenge and has been linked to increased engagement in deviant behaviors. However, the socioemotional mechanisms underlying this association, as well as factors that may buffer adolescents against its negative effects, remain underexplored. The current study investigated the longitudinal association between peer stress and deviant behaviors among Chinese adolescents, focusing on loneliness as a mediating mechanism and stress mindset as a moderator of the association between peer stress and deviant behaviors, as well as between peer stress and loneliness. Two-wave data were collected from 4897 adolescents (Mage = 13.34 years, SD = 0.64; 50.6% girls) in Sichuan Province, China, during the falls of 2023 (Time 1) and 2024 (Time 2). Adolescents completed self-report measures of peer stress, stress mindset, loneliness, and deviant behaviors. After controlling for sociodemographic covariates (i.e. age, gender, highest level of parental education, and subjective social status) and baseline loneliness, higher levels of peer stress at Time 1 significantly predicted greater deviant behaviors 1 year later. Mediation analyses indicated that loneliness at Time 2 partially mediated the association between peer stress and subsequent deviant behaviors. Furthermore, stress mindset moderated the direct association between peer stress and deviant behaviors; peer stress predicted greater deviant behaviors among adolescents who endorsed a stress-is-debilitating mindset, whereas this association was not significant among those with a stress-is-enhancing mindset. These findings shed light on a socioemotional pathway linking peer stress to adolescent deviant behaviors and highlight stress mindset as a potentially protective factor, thereby informing future intervention research on loneliness and stress mindset as potential targets for supporting adolescent adjustment in the context of peer stress.