An intervention designed to reduce heavy marijuana use among college students is showing promising results.

Marijuana is a commonly used substance during college, and studies have shown heavy use can have negative effects on brain development into one’s early 20s. It has been correlated with elevated dropout rates, lower grades, and mental health issues like anxiety and depression. However, there are few evidence-based marijuana misuse prevention programs available for college students.

So a research team at Colorado State University adapted an evidence-based intervention for reducing college student alcohol misuse, e-CHECKUP TO GO, which changes users’ common misperception that alcohol use is more widespread and accepted than it actually is.

The e-CHECKUP TO GO program targets “substance-use social norms,” or the perception of the prevalence and acceptability of alcohol use, which are strong predictors of whether college students are likely to engage in their own personal consumption. Previous research shows that college students who overestimate the extent and approval of alcohol use are more likely to drink.

About the study

The CSU research team adapted the e-CHECKUP TO GO to provide students with personalized feedback about how their perceptions of marijuana use compare to actual norms, as well as information about consequences of misuse and protective behavioral strategies, which are ways for students to moderate use. According to lead researcher Nathaniel Riggs, an associate professor in CSU’s Department of Human Development and Family Studies, the Marijuana e-CHECKUP TO GO intervention offers students customized feedback based on their survey responses and addresses the misperception that marijuana use is more widespread and has broader approval by others than is actually the case.

With the help of the CSU Health Network, the research team used Facebook, direct emails and flyers to recruit about 300 students who reported using marijuana at least twice a week. The team randomly divided the students into two groups and had them take an online survey about their marijuana use. The first group then participated in Marijuana e-CHECKUP TO GO, while the second group just received tips for stress reduction and healthy living.

Six weeks after they participated in the initial survey and intervention, both groups were surveyed again. The group that received only tips for stress reduction and healthy living showed no significant change in its responses. But the group that went through the Marijuana e-CHECKUP TO GO intervention reported decreased estimates of others’ use, fewer days per week and weeks per month in which they got high, greater number of days since their last use, and fewer time periods of being high each week. Sustained results were also found at a 12-week follow-up. Interestingly, participants originally assigned to the healthy stress management comparison group later received the e-CHECKUP TO GO and demonstrated similar, statistically significant decreases in their frequency of marijuana use.

Next steps

Future steps for the research team include comparing the effectiveness of this intervention in states with varying marijuana use policies (some allow adult recreational use, some allow only medicinal, and others ban it outright).

A challenge for future studies will be to increase retention; the number of participants had dwindled to 227 at the six-week mark. Riggs said researchers may be able to keep more of the participants in the study by increasing incentives. Participants in this project received a $20 gift card for the initial survey/intervention and $10 for each of the two subsequent check-ins, at six and 12 weeks. Those who participated in all three had a chance to win a $100 gift card.

In addition to Riggs, the other members of the research team were Melissa George, a research scientist in the Department of Human Development and Family Studies; Mark Prince, an assistant professor in CSU’s Department of Psychology; Brad Conner, an associate professor in CSU’s Department of Psychology; and Audrey Shillington, professor and head of CSU’s School of Social Work. Study findings were presented at the July 28-30 conference of the Research Society on Marijuana in Fort Collins.