PROJECT SUMMARY American Indian (AI) youth demonstrate early substance use initiation and subsequently high substance misuse rates. One factor contributing to this is the relative lack of prevention strategies that leverage contextual and cultural strengths to optimize effectiveness and sustainability. Rich cultural and traditional practices make interpersonal relationships particularly vital for AI youth, but these networks are largely untapped in prevention approaches. Research in other populations demonstrates social networks' roles in risk and resilience. However, data on AI social networks are sparse, and data on how networks relate to risk for early substance use is virtually nonexistent. Preliminary data from the Tribal Reservation Adolescent Connections Study (R21DA053789) confirmed suspicions that social network theories require some adaptation to the culture and context of AI communities. The proposed study will collect quantitative social network surveys among adolescents and community organizations and qualitative interviews with adolescents on a Northern Plains reservation to explore how these networks are structured, the principles under which they operate, and their influence on behavior over critical periods of adolescence. Network characteristics will be examined in relation to substance use, suicide, and exposure to violence, to understand how and when networks impact risk and resilience. A cohort sequential longitudinal and explanatory sequential mixed method design (QUAN → Qual) will be used to accomplish three specific aims: Aim 1: Identify changes in AI adolescents’ peer and kinship social networks over time. Hypothesis: Social network composition and structure will change from late childhood into late adolescence and those changes will include shifts in network size, proportion of family in networks, and gender homophily. Aim 2: Analyze community-based interorganizational networks among youth-serving institutions. Hypothesis: These networks will vary over time and location, resulting in varied coordination of youth services across communities. Aim 3: Test the relationship of peer, kinship, and community-based network characteristics to trajectories of substance use over time and in combination with violence and suicide. Hypothesis: Trajectories of substance use, violence, and suicide will be related and influenced by both stable and dynamic youth and community networks. This project will be led by a team of early-stage Principal Investigators who are American Indian and Alaska Native. They have expertise in substance use, exposure to violence and suicide among AIs, expertise in community-engaged research with tribal communities, social network analyses, and quantitative, qualitative, and mixed methods approaches. This leadership team will be supported by two senior researchers with experience in areas relevant to this study and 20 years of experience conducting research with the reservation where the study will take place and an expert in longitudinal social network analysis at the individual and community level.

PROJECT NARRATIVE Disproportionately high rates of early substance use among American Indian (AI) youth put them at greater risk for developmental disruption and long-term health consequences than their non-AI peers. Social network researchers have examined adolescents’ social networks and used them to enhance prevention; these efforts, however, have not reached AI communities. This longitudinal mixed methods study will collect social network data at the individual and community level to explore the structure and function of AI adolescent social networks and examine how network features relate to risk and protection for substance use, suicide, and exposure to violence over time.