The impact of school transitions on adolescent alcohol and tobacco use: Variations by network position and friendship stability.

The structural transition from middle to high school is an important life event that informs adolescents' engagement in delinquency. The current project considers whether this anticipated school change impacts rates of alcohol and tobacco use, particularly for youth in risky social network positions and who experience friendship instability. We analyzed a unique longitudinal sample of 14,465 adolescents from 51 school-based networks that participated in the PROSPER study. On average, students who changed schools between 8th and 9th grade reported significantly higher rates of drinking alcohol than youth who remained in the same building, while the transition did not impact smoking behaviors. High levels of popularity and maintaining previous friendships buffered the transition's negative impacts, though there were variations across substances. Results further our understanding of how social connections shape adolescents' experiences with key life transitions and carry implications for school programming.