Undergraduate Research at Virginia Tech

Exploring Reasons Behind Marijuana Use

By Jessica Cooper, marketing management major and honors student

Now a research assistant for the Department of Psychology's Addictions Research Lab, 2004 Virginia Tech alumnus Kristin McCants was bit by the research bug early on as an undergraduate. After volunteering to be a research assistant as a freshman, McCants, a psychology major with biology and chemistry minors, progressed to complete two field studies and a literature review by her junior year. It was during this time that her interest in the behavioral theories of humans was sparked, creating the foundation of her honors thesis. With the evidence that roughly 14 percent of people between the ages of 18 and 25 currently use marijuana, McCants sought to gain a better understanding of the decision factors to use or not use this widely abused illegal substance among college students.

After recruiting a participant pool of 181 users and nonusers, McCants used two main behavioral theories to provide a framework for her research. First, the Theory of Planned Behavior (TPB), which states that a person's intention is the most important predictor of volitional behavior, was used to examine each subject's attitudes, perceptions of social norms, and perceived control over his/her own behavior in relation to the use/nonuse of marijuana. Second, she used Expectancy Theory and the Marijuana Effect Expectancy Questionnaire (MEEQ) to measure an individual's perceived set of beliefs about the positive and negative effects of using marijuana.

With the framework and research participants in place, McCants began her experiment, testing three main hypotheses. First she sought to determine if the TPB would explain a significant variance in the prediction of the intent to use and the actual use of marijuana. Second, McCants examined the MEEQ to see if was a significant predictor of the intent to use marijuana and the actual behavior associated with marijuana use. Lastly, she was interested in whether or not the MEEQ was a better predictor of the intentions to use marijuana than the outcome beliefs and values associated with the TPB.

After all the research sessions were completed and the data was compiled, McCants' research results supported two of her three hypotheses. Her results showed that the components of the TPB accounted for 58.5 percent of the variance for the intention to use and 49.5 percent of the variance for actual marijuana use. Her findings also supported her second hypothesis that the MEEQ would provide additional predictive power of intention and actual use of marijuana, though her results were only marginally significant. Regarding her third hypothesis, while McCants was able to demonstrate that the MEEQ is a better measure of predicting intentions, she was not able to prove its success above and beyond simple global attitudinal measures, such as "marijuana is good/bad" or "unpleasant/pleasant."

The results of McCants' research can be used to help develop better prevention and intervention programs for users and nonusers of marijuana. Addiction specialists could make the negative effects of marijuana more salient to individuals, potentially helping to reduce both the intention to use and the actual use of marijuana. Like any good researcher, McCants realizes that there may be some limitations in her findings. First, because she used a homogenous sample of all college students, a sample bias may exist. Additionally, with 34 percent of her participants having never used marijuana, McCants recognizes that her research findings may be more effective in distinguishing between users and nonusers. Finally, McCants believes that testing a group of heavy and chronic users may produce more informative results when working with a treatment population.

With her experiment behind her, McCants is able to see the fruits of her labor. "It was an interesting and informative process all the way from conceptualization to defending my thesis," she said. While her topic was harder to assess than that of alcohol use since many people don't want to admit that they are using an illegal substance, McCants found the "hardest part was actually dealing with the stress of getting it done."

She is currently working as a research assistant with Associate Professor Robert Stephens, who supervised her undergraduate research, and plans to attend graduate school in the near future. "Doing my thesis through the honors program only solidified my desire to go to grad school," she said. Until then, McCants continues to gain invaluable research experience examining different strategies of addiction intervention programs.