PROJECT SUMMARY Intimate partner violence (IPV) and depression are substantial public health challenges for U.S. adolescents, and evidence suggests a clear link between IPV experiences and subsequent depression. Despite their co- occurrence and grave implications, research has not sufficiently explored the nuances and longitudinal patterns of these experiences. The proposed research study addresses the intersecting crises of IPV and depression, focusing on adolescents' unique vulnerability and the consequences of these issues for their short- and long- term well-being. This study leverages the nationally representative NEXT Generation Health Study (NEXT) dataset, which spans seven years of longitudinal data collected annually (2010–2017) from a diverse sample of 2,780 adolescents aged 15 through 23. The study examines the longitudinal relationship between IPV and depression via two specific aims. Aim 1) To identify and characterize subgroups of IPV experience from mid- to late-adolescence for females and males separately. Using Latent Class Analysis, this aim seeks to reveal distinct patterns of IPV experience during adolescence using the first four waves of the NEXT, which measure various types of IPV, including verbal, psychological, physical, and sexual. Subsequently, various background indicators (e.g., age, race/ethnicity, sexual orientation, household structure) will be explored as predictors of subgroup membership. Because previous research points to sex-specific differences in IPV experience, these analyses will be conducted separately for females and males. Aim 2) To examine depression symptom trajectories and the relationship between IPV subgroups and depression trajectories from mid-adolescence to young adulthood. Using dual trajectory modeling, this aim investigates longitudinal trajectories of depression for the full NEXT sample, and then within identified IPV subgroups, exploring variations in onset, duration, and severity of depression symptoms. It is hypothesized that individuals in subgroups described by more severe, persistent IPV will exhibit higher, more persistent depression trajectories over time compared to subgroups described by less persistent IPV experiences, with background indicators influencing these relationships. This study addresses a major gap in knowledge of the longitudinal relationship between adolescents’ IPV experiences and subsequent depression over longer time periods during the critical transition from adolescence to young adulthood, reflecting multiple NIH research priorities. Responsive to the NICHD Child Development and Behavior Branch’s strategic plan theme of improving child and adolescent health and the transition to adulthood and NIMH’s priority for mental health disparity research, this study will improve understanding of IPV and depression among adolescents as they transition to young adulthood. Findings are valuable for tailoring interventions and policies, as different subgroups may have unique ...