Modeling Peer Network Dynamics and Alcohol Use Throughout High School

About This Grant

Project Statement/Abstract. Adolescent alcohol use remains a major public health concern in the United States, with early initiation linked to long-term mental and physical health risks. Although overall prevalence has been declining in recent years, adolescents today engage in riskier patterns of alcohol consumption than before, including binge drinking and alcohol-induced blackouts. Peer relationships are a key influence on adolescent alcohol use. Adolescents both select peers with similar behaviors (peer selection) and are also influenced by their peers’ behaviors (peer influence). Social network analysis offers a powerful framework for examining these peer processes, but conceptual and methodological gaps remain in understanding how, when, and for whom they matter. Most existing studies rely on data collected in the 1990s and early 2000s, which do not account for the increasingly digital age and COVID-19 pandemic, both of which have shifted socialization. In addition, studies often assume that the effect of peer influence is constant across adolescence and overlook individual differences in network position or demographic characteristics like sex. This project will address those limitations using data from an NIH-funded, recently collected (2020-2024) longitudinal cohort study of high school students in Southern California. More than 3,000 students were surveyed once per semester throughout all of high school, resulting in eight waves of data on friendship nominations, alcohol use, and demographic characteristics. Retention exceeded 80% across all eight waves. These data provide a unique opportunity to model peer dynamics throughout high school as they relate to alcohol use. The project has three aims: 1) assess whether the association between peer alcohol exposure and individual use is moderated by an adolescent’s position in the network (i.e., centrality), 2) examine how alcohol use similarity contributes to the formation and dissolution of adolescent friendships and whether this differs by sex, and 3) determine when peer influence is most impactful during high school. This study will use lagged logistic regression models, temporal exponential random graph models, and time-varying effect modeling to test these three aims. This research will address key gaps in adolescent alcohol research by identifying who is most vulnerable to peer influence, how peer selection operates, and when prevention efforts may be most impactful. Findings will inform the development of network-based, developmentally timed prevention strategies and advance understanding of the social and developmental etiology of alcohol use. This project also offers a rigorous training platform in longitudinal network analysis and adolescent alcohol use, supporting the applicant’s development as an NIH-funded prevention scientist.