Aggression mediates the association between problematic smartphone use and cyberbullying perpetration: a 6-year longitudinal study of Korean adolescents.

Introduction: Cyberbullying perpetration is a form of interpersonal violence among adolescents that is associated with mental health risk factors and outcomes, yet the longitudinal mechanisms linking problematic smartphone use (PSU) to cyberbullying remain unclear. Guided by the General Aggression Model, this study examined whether aggression mediates the relationship between PSU and cyberbullying perpetration and whether parental structuring moderates this indirect pathway. Methods: The study utilized six waves of nationally representative panel data from 2,242 Korean adolescents participating in the Korean Children and Youth Panel Survey. Generalized estimating equation models were applied to test longitudinal mediation and moderated mediation across adolescence. PSU was specified as the independent variable, aggression as the mediator, cyberbullying perpetration as outcome, and parental structuring as the moderator. Covariates included sleep duration, leisure time, physical activity, smartphone usage time, and peer relationships. Results: PSU was significantly associated with increased aggression over time, which subsequently was associated with increased cyberbullying perpetration, indicating an indirect pathway. Parental structuring was associated with a stronger PSU -aggression relationship during adolescence rather than buffering it. Aggression functioned as a key mechanism linking PSU to cyberbullying perpetration, and this pathway was stronger among adolescents reporting higher levels of parental structuring. Discussion: These findings suggest that parental regulation of adolescent smartphone use alone may be insufficient, and that prevention of cyberbullying requires multilevel interventions integrating school- and community-based programs and developmentally appropriate strategies targeting online risk behaviors.