Parental and early childhood predictors of persistent physical aggression in boys from kindergarten to high school

dBackground: In a prior study, we identified F groups following distinct de velopmental courses, or trajectories, of physical aggression in 1037 boys f rom 6 to 15 years of age in a high-risk population sample from Montreal, Qu ebec. Two were trajectories of high aggression, a persistently high group a nd a high but declining group. The other 2 trajectories were a low group an d a moderate declining group. This study identified early predictors of phy sical aggression trajectories from ages 6 to 15 years. Methods: In this study, logistic regression analysis was used to identify p arental and child characteristics that distinguished trajectory group membe rship. Results: For buys displaying high hyperactivity and high opposition in kind ergarten, the odds of membership in the 2 high aggression groups were incre ased by factors of 3.0 (95% confidence interval [CI], 2.0-4.3) and 2.7 (95% CI, 1.9-3.8), respectively, compared with boys without these risks. Counte rpart odds ratios for the risk factors of mothers' teen-onset of parenthood and low educational attainment were 1.6 (95% CI, 1.1-2.2) and 1.8 (95% CI, 1.3-2.4), respectively). Only the maternal characteristics distinguished b etween the trajectory of persistently physical high aggression and the traj ectory starting high but subsequently declining. For the 2 maternal risk fa ctors combined, the odds ratio of persisting in high level physical aggress ion was 9.4 (95% CI, 2.9-30.4). Conclusions: Kindergarden boys displaying high levels of opposition and hyp eractivity are at high risk of persistent physical aggression. However, amo ng kindergarten boys who display high levels of physical aggression, only m others' low educational level and teenage onset of childbearing distinguish those who persist in high levels of physical aggression.