Reasons I Choose Not to Use Marijuana: Exploratory Factor Analysis of Young Adult Motivations for Marijuana Non-Use and Group Differences By Level of Use

Introduction: Motivational models of substance use suggest behavior is motivated by various reasons; however, few studies have examined motivations for not using marijuana. Reasons for abstinence, as well as non-use on specific occasions, could guide the content of prevention and intervention efforts. The goal of this study was to examine the psychometric properties of a multi-faceted measure of motivations for not using marijuana and explore differences in reasons based on marijuana use. Methods: Data (N = 390, 50% female, 59% Caucasian) were collected from young adults ages 18-23 years (M = 20.70, SD = 1.65). A 30-item measure asked participants to indicate the extent to which they chose not to use marijuana, either at all or on specific occasions (0 = not at all to 4 = very much). Exploratory factor analysis with promax rotation was conducted. One-way analysis of variance (ANOVA) tested for group differences based on level of marijuana use (lifetime abstainers [n = 90], past users [n = 127, used in past but not in last 30 days], current users [n = 173, used in last 30 days]). Results: As identified by the Minimum Average Partial (MAP) test and parallel analysis, a 5-factor solution of reasons for not using marijuana was retained: Physical, legal, and personal consequences (11 items, Cronbach’s α = .90); Side effects and loss of energy (7 items, α = .85); Other responsibilities (4 items, α = .72); Lack of availability (3 items, α = .67); Not interested (3 items, α = .69). Two items were excluded based on the 5-factor solution. One-way ANOVAs showed that all three groups were significantly different from each other on 3 of the 5 factors: Physical, legal, and personal consequences (R² = .30), Side effects and loss of energy (R² = .10), and Not interested (R² = .23). For each subscale, lifetime abstainers had significantly higher scores (i.e., endorsed reasons more frequently) than past and current users; past users also had significantly higher scores than current users. For the other responsibilities subscale (R² = .02), lifetime abstainers had significantly higher scores than current users. Lastly, for the lack of availability subscale (R² = .05), both lifetime abstainers and past users had significantly higher scores than current users. Conclusions: Lifetime abstainers and past users endorsed numerous reasons for not using marijuana including potential serious negative consequences (e.g., arrest, long-term physical problems) and side effects (e.g., loss of energy or motivation); these motivations could be targeted and reinforced in prevention messages. Further research is needed to understand current users’ reasons for not using on specific occasions, as the ones currently assessed do not appear to be salient or frequently endorsed.