Project Summary Young victims of community violence whose injuries are severe enough to warrant an Emergency Department (ED) visit are at high risk for developing posttraumatic stress symptoms (PTSS) and other psychiatric, functional and behavioral issues. They are also at high risk for retaliatory behaviors, re-injury and death and according to an AHRQ sponsored meta-analysis there is no evidence of effective treatment to prevent PTSS in violently injured youth. The proposed research is designed to test a novel approach to support and expedite the recovery of assaulted youth and their families. We propose to conduct a Randomized Clinical Trial evaluating the effectiveness of the Child and Family Traumatic Stress Intervention (CFTSI) in reducing PTSS in youth 10-18 years old who are also receiving Case Management (CM) after an assault injury. CFTSI is a 4-6 session manualized intervention focused on improving communication between the caregiver and their child about their PTSS in order to enhance a key protective factor: caregiver emotional support. It is the first intervention demonstrating effectiveness in preventing posttraumatic stress disorder (PTSD) and decreasing PTSS in youth traumatized by a range of trauma types (a small subset of the sample were assault injured youth) when delivered within 45 days of a traumatic event, but has not been fully studied in youth who have been assault-injured or in conjunction with a hospital-initiated Case Management (CM) program. Post- discharge CM is an emerging standard of care throughout large medical center EDs and trauma units, whereby assault-injured youth receive a comprehensive psychosocial assessment, navigation to a range of medical, housing, behavioral health, recreational, vocational and other services. The aims and hypotheses propose that CFTSI will significantly reduce PTSS in assault-injured youth and a participating parent, measured 4 months and 10 months after enrollment into the study. In addition, we will evaluate the mechanisms of communication and parental support and investigate mediators and moderators of the effect of CFTSI on PTSS. The study will also explore how CFTSI influences retaliatory attitudes, re-injury and general health after being victimized, and will elucidate the mechanisms involved in child and family-level recovery in the months after an assault. The research literature supports that individuals with PTSS have a range of poor psychosocial outcomes. Reducing significant PTSS (primary aim) after assault injury provides an important way by which to reduce the risk of further adverse outcomes. The proposed study advances the aims of the NICHD Pediatric Trauma and Critical Illness Branch to perform “research on prevention, treatment, management, and outcomes of physical and psychological trauma and the surgical, medical, psychosocial, and systems interventions needed to improve outcomes for critically ill and injured children across the developmental trajectory.”