Abstract
We investigated the associations between same-gender friendship, gender reference group identity, and substance use in college students (54 % male, M age = 19.23, SD = 1.23) from the northeastern United States using an online survey. Male students reported greater weekly marijuana, but not alcohol use than female students. Regression analyses revealed that having a greater proportion of same-gender friendships was associated with greater weekly alcohol use for male students and lesser weekly alcohol and marijuana use for female students. Gender reference group identity was negatively associated with weekly marijuana use for male and female students. For female students, gender reference group identity mediated the association between proportion of same-gender friendships and weekly marijuana use. Our study highlights the importance of considering the social context (e.g., the gender of friends) and individual variables relating to gender (e.g. gender reference group identity) in substance use research. Our findings fit within social constructionist models of social development that suggest participation in gendered contexts (e.g., same-gender or other-gender-peer contexts) over time cue gender-typed behaviors such as using marijuana.