Developing Trauma Networks of Children, Adolescents, and Young Adults to Examine the "Ripple Effect" of Firearm Injuries - PROJECT SUMMARY/ABSTRACT Firearm injury and death is a public health epidemic that spreads through communities and social networks in the United States much like an infectious disease. Individuals who survive a firearm injury (i.e., nonfatal survivors), experience increases in the risk of adverse health outcomes, such as posttraumatic stress disorder (PTSD), anxiety, and depression. Family members of homicide victims, nonfatal firearm injury survivors (i.e., secondary survivors), and communities more broadly are also affected. Due to methodological limitations, we have very little data on what trauma networks (defined as individual(s) present at a shooting event and/or family member(s) of a fatal victim/nonfatal survivor) look like and much less on the long-term health effects of being in the network of a firearm injury. This is a critical question because these trauma networks – people exposed but not injured – are likely at high risk of adverse health outcomes, particularly children, adolescents, and young adults (CAYA) and are currently being missed in firearm injury focused interventions. The proposed study will use an existing data repository (used in prior work) of individually linked records from healthcare and police data between 2016 - 2022. We specifically aim to 1) develop and describe trauma networks of all individuals (i.e., victims, witnesses per police data) present at a shooting event and/or all family members of firearm injury victims/survivors per Medicaid data and 2) examine clinical utilization, firearm injury, and mortality outcomes among CAYA network members, due to the high risk of adverse health outcomes in the 5-years following firearm injury event. This study will demonstrate defining trauma networks to identify CAYA exposed to firearm injury is feasible (Aim 1) and estimate prevalence rates of mental health outcomes, firearm injury, and mortality among network members (Aim 2) in order to identify future opportunities for interventions. SIGNIFICANCE: Consistent with the NICHD strategic plan, our methodology, data infrastructure, and composition of our research team ensures that our research will significantly extend our understanding of the mechanisms and impacts of firearm injury events beyond the individual directly involved to improve health across the lifespan. Regardless of the results, this will lead to a R01 application addressing the health needs among CAYA within trauma networks and inform interventions that may mitigate adverse and likely debilitating effects among CAYA and will have implications for broader public health significance.