Peer‐Aggression Victimization and Perpetration in Middle School Youth: Estimating Prevalence and Frequency, Joint Trajectory Patterns, and Predictive Utility

The purpose of this study was to examine early adolescent trajectories of bullying/peer-aggression in terms of their prevalence, composition, and ability to correlate with concurrent delinquency. Three hypotheses were tested in a group of 1145 middle school students (49.6% male; mean age = 11.23 years) using longitudinal data spread out over three waves. The first hypothesis predicted that bullying/peer-aggression victimization would be significantly more prevalent and frequent than bullying/peer-aggression perpetration. The second hypothesis held that a semiparametric sequential process growth mixture modeling (GMM) analysis for two latent variables would identify pure victim and mixed victim-perpetrator trajectories but no pure perpetrator trajectories. The third hypothesis asserted that the trajectory models identified in the GMM analysis would differentially correlate with a change in delinquency, such that accelerating trajectories would be associated with a rise in delinquency and decelerating trajectories with a drop in delinquency. Analyses provided support for all three hypotheses: victimization was significantly more prevalent and frequent than perpetration; there were no pure perpetration trajectories, even after increasing the number of trajectories from 6 to 9; and accelerating trajectories were associated with a significant rise in delinquency from Wave 1 to Wave 3 and decelerating trajectories with a marginally significant decrease in delinquency from Wave 1 to Wave 3. These results highlight the value of studying change in the perpetration and victimization of peer-aggression as a way of understanding how bullying/peer aggression in early adolescence develops and contributes to the formation of other problems, such as delinquency.