Peer Connectedness and Substance Use in Adolescence: A Systematic Review and Meta-Analysis

Objective: Adolescents' relationships with their peers play a pivotal role in their substance-use behaviors. As such, decades of research have examined how substance use relates to adolescents' overall levels of closeness to their peers, here termed peer connectedness, with mixed results. This report sought to determine how the operationalizations of peer connectedness and substance use affect the nature of the relationship between them. Method: We used a systematic review strategy to find a comprehensive set of studies investigating the relationship between peer connectedness and substance use. Three-level meta-analytic regression was used to empirically test whether the operationalization of these variables moderates effect sizes across studies. Results: We found 147 studies, of which 128 were analyzed using multilevel meta-analytic regression models. Operationalizations of peer connectedness varied widely, encompassing sociometric and self-report measures. Of these measures, sociometric indices specifically pertaining to popularity were most strongly predictive of substance use. Less consistent relationships were observed between substance use and sociometric measures of friendship, as well as with self-report measures. Conclusions: Being perceived as popular by one's peers is positively related to substance use among adolescents. This relationship is stronger and more consistent than those between substance use and other peer-connectedness variables, underscoring the necessity of operationalizing these constructs specifically and clearly. Public Health Significance Statement This review comprehensively explores the links between peer connectedness in adolescence and different types of substance-use behavior, allowing for a clearer understanding of exactly which adolescents are at the greatest risk for the most dangerous substance-use behavior.