Understanding Which Teenagers Benefit Most From a Brief Primary Care Substance Use Intervention

The primary care (PC) setting provides an opportunity to address adolescent alcohol and marijuana use. We examined moderators of effectiveness for a PC brief motivational intervention on adolescents' alcohol and marijuana use and consequences 1 year later.

We conducted a randomized controlled trial in 4 PC clinics from April 2013 to November 2015 and followed adolescents using Web-based surveys. We examined whether demographic factors and severity of use moderated 12-month outcomes. Adolescents aged 12 through 18 were screened by using the National Institute on Alcohol Abuse and Alcoholism Screening Guide. Those identified as at risk were randomly assigned to the intervention (CHAT) or to usual care (UC).

The sample (n = 294) was 58% female, 66% Hispanic, 17% African American, 12% white, and 5% multiethnic or of other race with an average age of 16 years. After controlling for baseline values of outcomes, teens in CHAT who reported more negative consequences from drinking or had an alcohol use disorder at baseline reported less alcohol use, heavy drinking, and consequences 1 year later compared with teens in UC. Similarly, teens in CHAT with more negative consequences from marijuana use at baseline reported less marijuana use 1 year later compared with teens in UC; however, teens in CHAT who reported fewer marijuana consequences at baseline reported greater marijuana use 1 year later compared with teens in UC.

A brief intervention can be efficacious over the long-term for adolescents who report problems from alcohol and marijuana use. Findings emphasize the importance of both screening and intervention in at-risk adolescents in PC.