News Release

Co-use of alcohol and marijuana and beliefs among teens

Peer-Reviewed Publication

Pacific Institute for Research and Evaluation

New research from the Prevention Research Center of the Pacific Institute for Research and Evaluation examines whether recreational marijuana legalization in Oregon and marijuana and alcohol retail outlet density levels are associated with co-use and beliefs supportive of use of each among teens.

Using data from 11th graders who participated in the Student Wellness Survey from 2010-2018, researchers assessed past-30-day co-use changes in counties with low, medium, and high densities of licensed marijuana and alcohol outlets.

Findings include:

  • A significant post-legalization increase in past-30-day co-use in 2016 in counties with the highest retail outlet density.
  • Significant post-legalization increases in perceived risk and parent approval of alcohol and marijuana use.
  • Legalization and greater retail availability of both marijuana and alcohol were positively associated with co-use among teens, and beliefs favorable to alcohol and marijuana use.

Says lead author, Dr. Grisel García-Ramírez: "Our results suggest that adolescents living in communities with greater retail availability of recreational marijuana and alcohol may have greater indirect access to these substances through diversion, as it is illegal for them to purchase and use them. So, their primary sources are likely to be social rather than commercial."


Source: García-Ramírez, Grisel, Mallie J. Paschall, and Joel W. Grube. "Retail Availability of Recreational Marijuana and Alcohol in Oregon Counties and Co-Use of Alcohol and Marijuana and Related Beliefs among Adolescents." Substance Use & Misuse (2020): 1-8.

PIRE is an independent, nonprofit organization merging scientific knowledge and proven practice to create solutions that improve the health, safety and well-being of individuals, communities, and nations around the world.

The Prevention Research Center (PRC) of PIRE is one of 16 centers sponsored by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), of the National Institutes of Health, and is the only one that specializes in prevention. PRC's focus is on conducting research to better understand the social and physical environments that influence individual behavior that lead to alcohol and drug misuse.

The Resource Link for Community Action provides information and practical guidance to state and community agencies and organizations, policy makers, and members of the public who are interested in combating alcohol and other drug abuse and misuse.


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