TitlePerceived prevalence of peer marijuana use: changes among college students before and after Oregon recreational marijuana legalization.
Publication TypeJournal Article
Year of Publication2019
AuthorsKoval, AL, Kerr, DCR, Bae, H
JournalAm J Drug Alcohol Abuse
Volume45
Issue4
Pagination392-399
Date Published04/2019
ISSN1097-9891
Abstract

Background

Oregon students' rates of marijuana use have increased following recreational marijuana legalization (RML), but the relation between RML and students' perceived peer use of marijuana - or descriptive norms - is unknown.

Objectives

This study examined whether perceived peer use of marijuana changed more following RML for college students in Oregon than in states without RML.

Methods

Repeated cross-sectional data were collected from the National College Health Assessment-II surveys from 2008 to 2016 to assess changes in descriptive norms ("Within the last 30 days, what percent of students at your school used marijuana?") among 18-26 year-old undergraduates from two Oregon institutions and 123 institutions in non-RML states (N = 280,006; 66.23% female; 33.19% male) following Oregon RML (7/1/2015). Mixed-effects regressions were used to account for clustering at the institutional level; models controlled for covariates and secular changes in descriptive norms.

Results

RML was associated with higher perceived rates of marijuana use by peers [Percent Increase = 3.09, p < .001]. The effect was significant for respondents who had never used marijuana [Percent Increase = 3.72, p < .001], but not for respondents who recently or ever previously used marijuana. Respondents who had recently used marijuana had higher descriptive norms than those who had never used [Percent Increase = 12.83, p < .001].

Conclusions

Given the association between descriptive norms and personal use, RML-related increases in descriptive norms among non-using students could contribute to future marijuana use initiation and may be one mechanism linking RML with higher rates of marijuana use among college students.

DOI10.1080/00952990.2019.1599381
Alternate JournalAm J Drug Alcohol Abuse
PubMed ID30990356