An examination of the shift in school-level clustering of US adolescent electronic cigarette use and its multilevel correlates, 2011-2013.

The percent of US high school students reporting use of electronic cigarettes (i.e., e-cigarettes) tripled in recent years. Little is known about the temporal shifts in school-level e-cigarette prevalence or the multilevel correlates of teen e-cigarette use. Using multilevel regression techniques and data from the 2011 and 2013 US National Youth Tobacco Surveys, we investigate how the school-level clustering of e-cigarette use has shifted between 2011 and 2013, whether school-level e-cigarette use is associated with individual-level use, and whether this association is explained by perceptions of harm attributed to e-cigarettes. Results indicate that school-level clustering of pastmonth e-cigarette use increased between 2011 and 2013. Multilevel models show that school-level e-cigarette use is positively associated with individual use, with a small proportion of this relationship explained by perceived harm of e-cigarettes. Our findings suggest that schools could have become more differentiated from each other based on their prevalence of e-cigarette use, and that certain types of school environments facilitate e-cigarette use more efficiently than others.