Examining within-person and between-person associations of family violence and peer deviance on bullying perpetration among middle school students.

Objective: Family violence and peer deviance have shown to be related to bullying perpetration. Although there are several cross-sectional investigations of these two factors in relation to bullying behavior, no known studies have examined their interactive associations. The current study examines the longitudinal associations of both factors on bullying perpetration using a multi-level approach. Method: Participants included 1,194 5th, 6th, and 7th grade students from four middle schools in a Midwest county. We examined the main and interactive relations between how individual reports of family violence and peer deviance fluctuated over time (i.e., within-person effects) and how average reported differences between individuals (i.e., between-person effects) were associated with levels of bullying perpetration. Results: Positive main effects were found for both family violence and peer deviance on levels of bullying perpetration. Within-person effects indicated that, on average, fluctuations from one's 'typical' levels in family violence and peer deviance were associated with contemporaneous increases in bullying perpetration. A statistically significant time-variant interaction revealed that within-person family violence significantly exacerbated the relationship between within-person peer deviance and bullying perpetration. Furthermore, a statistically significant cross-level interaction revealed that the association between within-person peer deviance and bullying perpetration was stronger for individuals with higher average levels of between-person family violence (+1SD) compared to lower levels (-1SD). Implications: These findings provide a more nuanced lens from which to view the co-occurring relations between family and peer ecologies. Prevention and intervention efforts should target peer relations to reduce the effect of family violence on bullying behavior.