E-Cigarette Use Behavior and Expectancies Among Sexual Minority and Heterosexual College Student E-Cigarette Users.

College students who identify as a sexual minority (i.e., lesbian, gay, bisexual, or other sexual orientation) are at higher risk for e-cigarette use than their heterosexual or "straight" peers. However, little is known about factors, such as e-cigarette outcome expectancies, that might influence these differences in prevalence rates. Therefore, the current study examined differences between heterosexual and sexual minority college student e-cigarette users in terms of days of past-month e-cigarette use, e-cigarette dependence, and e-cigarette outcome expectancies. A secondary aim of the study was to examine whether outcome expectancies served as an explanatory mechanism in the association between sexual minority status and e-cigarette use frequency and dependence. Participants were heterosexual ( = 90; = 19.65,  = 2.70; 76.7% female; 77.8% White) and sexual minority ( = 44; = 20.02,  = 2.18; 68.2% female; 90.9% White) college student e-cigarette users who completed self-report measures. Students who identified as a sexual minority reported greater e-cigarette dependence, more frequent past 30-day use, and greater negative consequences and positive reinforcement e-cigarette outcome expectancies. Follow-up mediation analyses indicated a significant indirect effect of sexual minority status on both days of past-month e-cigarette use and e-cigarette dependence through expectancies for negative consequences and positive reinforcement. These findings suggest that positive reinforcement and negative consequences outcome expectancies may be contributing to the disparities in e-cigarette use among college students who identify as a sexual minority and could be useful targets for cessation interventions for this population.