PROJECT SUMMARY / ABSTRACT Each year, millions of children sustain injuries and undergo invasive medical procedures in the emergency department (ED). Current guidelines emphasize the need to address the significant pain and distress children experience in the ED, but inadequate pain and distress management remain prevalent. Under-treated pain and distress can result in negative future pain experiences and maladaptive psycho-behavioral outcomes. Recent work suggests that Latinx children are at a particularly high risk for experiencing distress and pain surrounding surgery as well as pain treatment disparities in the ED. This application proposes a large-scale observational, longitudinal cohort study to identify both predictors and outcomes of procedural distress and pain in an ethnically diverse sample of children 2-9 years old undergoing invasive ED procedures. Methods will be based on the NIMHD Minority Health Disparities Research Framework and Triple Aim and will include empirically informed assessments of psychological, sociocultural, environmental, healthcare system, clinical recovery, patient experience, and resource utilization variables. The K23 candidate is an Assistant Professor at the University of California-Irvine School of Medicine and aims to establish an independent interdisciplinary research program that improves pediatric pain care and prevents adverse outcomes and healthcare disparities surrounding injury and painful procedures in the pediatric ED. The candidate’s training plan capitalizes on the expertise of a highly experienced multidisciplinary mentorship team, integrating key training in pain surrounding invasive ED procedures, Triple Aim value-based care framework, sociocultural factors in pediatric pain and pediatric healthcare disparities, advanced statistical modeling, and professional development. This application will be executed within the UCI Center on Stress & Health, a highly productive, well-established research environment that incorporates a unique multidisciplinary approach to training and clinical research. The training plan will incorporate didactic coursework, one-on-one mentoring, and UC Irvine Institute for Clinical and Translational Science (NIH CTSA) resources and seminars focused on career development, training evaluation and research ethics. With enthusiastic and material support from the Children’s Hospital of Orange County senior leadership, the project will be conducted in a high-volume pediatric ED where a large proportion of patients (66%) are Latinx and are part of an innovative population health program. Collectively, this will provide an exceptional training environment to characterize multidimensional contributors to procedural pain and distress in a population at-risk for experiencing care disparities and launch a clinically impactful, independent research program that promotes effective and equitable pediatric pain and injury-related care in the ED.