Heather Brittain, Tracy Vaillancourt
Bullying victimization, internalizing symptoms, and academic functioning are closely linked across adolescence, yet little is known about how these domains interact over extended developmental periods or across key school transitions. Using eight annual waves of data from a community cohort followed from Grade 5 to Grade 12 (N = 701; Mage = 10.91 years), we applied an auto-regressive latent trajectory model with structured residuals to separate between-person differences in developmental trajectories from within-person fluctuations. At the between-person level, higher bullying victimization was associated with higher internalizing symptoms and lower GPA. At the within-person level, bullying victimization and internalizing symptoms were tightly coupled across development, with internalizing symptoms predicting bullying victimization across the transition to secondary school. In secondary school, higher internalizing symptoms were associated with lower GPA and higher absences within-time. Across time, higher internalizing symptoms were associated with lower GPA, which in turn was related to higher absences. Findings indicate transactional cascades, with interconnections among peer, emotional, and academic domains and suggest that the transition to secondary school marks a period of heightened vulnerability. Results underscore the importance of early and sustained interventions that integrate bullying prevention, mental health support, and school engagement.