Relations between higher- and lower-order alcohol and cannabis expectancies and simultaneous use frequency among undergraduate dual users

Abstract Background Simultaneous alcohol and cannabis (i.e. marijuana; [SAM]) use is prevalent among college students. There is limited research on expectancy effects for SAM use, which are known correlates of use frequency and mediators of treatment outcomes. We examined the unique associations of both positive and negative alcohol and cannabis expectancies with frequency of SAM use among college students. Method Participants were 1012 college students (70.9% female, 51.8% white, M age = 19.63) from seven US universities who reported past-month alcohol and cannabis use (77.2% of the sample reported SAM use). Students completed measures of past-month typical weekly alcohol and cannabis frequency and quantity, alcohol and cannabis expectancies, and SAM frequency through an online self-reported survey. Results A negative binomial regression revealed that higher-order positive, but not negative, alcohol and cannabis expectancies were significant predictors of SAM frequency above and beyond frequency of alcohol and cannabis use, biological sex, and whether the survey was completed pre- or post-COVID-19 campus closures. Specifically, higher frequency SAM use was associated with weaker positive alcohol and stronger positive cannabis expectancies. A second negative binomial regression including lower-order expectancies found that SAM frequency was associated with weaker social and cognitive and behavioral impairment alcohol expectancies and stronger sexual and social facilitation cannabis and liquid courage alcohol expectancies, specifically. Conclusions Results highlight the importance of comprehensively examining both higher- and lower-order alcohol and cannabis expectancies when examining SAM frequency, and provide avenues of targeted intervention to reduce SAM use among dual users.