Developmental trajectories toward violence in middle childhood: course, demographic differences, and response to school-based intervention.

The present study addressed 3 questions concerning (a) the course of developmental trajectories toward violence over middle childhood, (b) whether and how the course of these trajectories differed by demographic subgroups of children, and (c) how responsive these trajectories were to a universal, school-based preventive intervention. Four waves of data on features of children's social-emotional development known to forecast aggression/violence were collected in the fall and spring over 2 years for a highly representative sample of 1st to 6th grade children from New York City public elementary schools (N = 11,160). Using hierarchical linear modeling techniques, synthetic growth curves were estimated for the entire sample and were conditioned on child demographic characteristics (gender, family economic resources, race/ethnicity) and amount of exposure to components of the preventive intervention. Three patterns of growth--positive linear, late acceleration, and gradual deceleration--characterized the children's trajectories, and these trajectories varied meaningfully by child demographic characteristics. Most important, children whose teachers taught a high number of lessons in the conflict resolution curriculum demonstrated positive changes in their social-emotional developmental trajectories and deflections from a path toward future aggression and violence.