Project Summary Child sexual abuse (CSA) is an adverse childhood experience with wide ranging effects on health, wellbeing, and development throughout the lifespan. The long-term goal of this Stephen I. Katz, Early-Stage Investigator R01 is to develop novel, targeted prevention approaches for recurrent CSA, a new research direction for the PI (Kobulsky). The objectives are to illuminate the etiology of recurrent CSA and to conceptualize prevention models within child welfare systems.To accomplish this, we propose a mixed methods practitioners at the Philadelphia Philadelphia design to reduce recurrent CSA via Children's Alliance (PCA, Child Advocacy Center) Department of Human Services (DHS; jurisdictional CPS agency). Our team of experts on existing partnerships among Temple University researchers, , and administrators in the CSA prevention, data science, geographic spatial analysis, qualitative and mixed methods, and health equity, positions us to create and analyze a unique linked longitudinal dataset, and to conceptualize prevention that will integrate research findings and the perspectives of multiple system constituents. Aim 1 is to curate a comprehensive longitudinal dataset from 2013-2021 including both CPS and law enforcement-investigated cases of CSA. We will leverage state-of-the-art data science techniques to create the dataset through the linkage of the PCA and DHS administrative data (Aim 1a). Natural language processing will be applied to extract data elements from free text fields, (Aim 1b) and geocoding to link neighborhood-level information. This unique dataset allows us to conduct a rigorous study of CSA and gain new insights into the prevalence and contributing risk and protective factors to CSA over time. Aim 2 is to illuminate the multilevel etiology of recurrent CSA. The aim will apply shared frailty survival analyses and spatial survival analysis to the dataset created in Aim 1 in order to identify the most potent predictors of recurrent CSA over time. It will examine the influences of CSA characteristics (Aim 2a), and social determinants of health (SDH) at the family (Aim 2b) and neighborhood (Aim 2c) levels on CSA recurrence. Aim 3 is to conceptualize prevention models for recurrent CSA. Qualitative interviews with multidisciplinary workers from the Philadelphia child welfare system, non-offending caregivers, and survivors will elicit interpretation of Aim 1 and 2 findings to enrich our theoretical model and conceptualize novel recurrent CSA prevention. Using a cutting-edge, mixed-method design, this project will illuminate the etiology of recurrent CSA and present significant new avenues for CSA prevention embedded within child welfare systems. This grant is an essential first step in a R34 NIH planning grant to develop novel, targeted CSA prevention, a new research agenda for the PI that can advance life course health and development for survivors of CSA.