Parallel Process of Posttraumatic Stress and Externalizing Problems Among Youth at High Risk for Victimization.

Research shows comorbidity between posttraumatic stress symptoms (PTSS) and externalizing problems among polyvictimized youth. However, the impact of polyvictimization on the longitudinal co-development of PTSS and distinct forms of externalizing problems remains unclear. Growth trajectory modeling was used to address this gap. At ages 8, 12, and 16, polyvictimization was measured using youth, caregiver, and official records; whereas youth self-reported PTSS and caregivers reported aggression and delinquency. Results demonstrate that changes in PTSS and each externalizing domain were independent. Further, polyvictimization and PTSS/aggression were only associated at concurrent time points. In contrast, polyvictimization and delinquency were generally associated at concurrent and distal time points, suggesting that polyvictimization may have a more enduring impact on youths' delinquent behaviors than other symptoms.