Contexts of Marijuana Use: A Latent Class Analysis among Argentinean College Students

Background: Substance use and the association between substance-related variables and outcomes seem to be context dependent. We employed Latent Class Analysis (LCA), a person-centered approach, to identify distinct subpopulations based on contexts of marijuana use. We also examined whether the resulting classes differ in a set of marijuana-related variables that hold promise as potential targets of interventions. Method: A sample of 1083 Argentinean college students (64% women; M age = 19.73±3.95) completed an online survey that assessed substance use and related variables (motives for substance use, protective behavioral strategies [PBS] and internalization of the college marijuana use culture). For the present study, only data from students that reported last month (i.e., past 30-day) marijuana use (n = 158) were included in the analysis. Participants reported whether or not they used marijuana in different places (i.e., own house, party at home, friends’ house, parties at friends' house, university party, non-university party, bar, dance-club, outside [street, park], or pregaming) or social contexts (i.e., alone, with family members, strangers, boyfriend/girlfriend, close friend, small group of same-sex friends, ≥10 same-sex friends, small co-ed group of friends, ≥10 co-ed friends). Results: LCA identified a 2-classes model for marijuana use context. Class 1 comprised 40% of last-month marijuana users. Students within this class endorsed a high probability of consuming marijuana across different places (e.g., at home, at parties, outdoors) and social contexts (e.g., close friend and in small same sex and coed groups). Participants in Class 2 exhibited a low endorsement of marijuana use across contexts, yet they reported a moderate to high probability of using marijuana with a small group of same-sex friends or with the close friend, at a friend’s home. The two classes significantly differed, as shown by Student’s t, on all marijuana outcomes (i.e., use and negative consequences) and marijuana-related variables (motives, PBS and internalization of the college marijuana use culture). Students in class 2 exhibited significantly less marijuana use, both in terms of frequency and quantity, and less marijuana-related negative consequences than those in class 1. The latter class exhibited more normative perceptions about marijuana use in college, more marijuana use motives -particularly social, coping and expansion motives- and less use of PBS than students in class 2 did. Conclusions: Our findings revealed subpopulations of college students that are heterogeneous regarding contexts of marijuana use, patterns of use and in a number of relevant variables. These distinctive subpopulations require different targeted interventions.