Developmental trajectories of girls' and boys' delinquency and associated problems.

Developmental trajectories in delinquency through adolescence were studied along with family and peer relationship problems. Drawing from eight waves of data over seven years, we conducted trajectory analyses with a sample of 746 students (402 girls; 344 boys). Analyzing girls and boys together, a five-class model emerged: 60% of the adolescents rarely reported delinquency; 27.7% reported low initial levels with moderate levels of delinquency over time; 6% in the late onset group reported initially low and rising levels of delinquency; 5% in the early onset group reported moderate initial levels which increased and then decreased in later adolescence. A small group of only boys (1.3%) labeled chronic reported high initial levels of delinquency that increased over time. Group comparisons revealed problems in internalizing, parent and peer relationship problems. The findings provide direction for early identification and interventions to curtail the development of delinquency.