The goal of this study is to assess the efficacy of a new intervention based on motivational enhancement therapy among adolescents with a history of substance use.

In many parts of the U.S. adolescent substance abuse treatment is scarce. Several studies have shown that brief interventions increase the likelihood of patients' completion of referrals to alcohol counseling or treatment. Other studies have shown a direct effect of brief interventions on patients' alcohol consumption. Although brief interventions have been widely recommended for adolescents, fewer studies have been conducted in this age group. If the current study confirms the effectiveness of the Motivational Enhancement Therapy approach, this will add another outpatient treatment option for adolescent patients with drug problems.

The specific aims of the project are to:

1. Test the effect of the brief intervention on drug use. We hypothesize that, among 12-18 year old medical patients who use drugs, the experimental intervention (two 60-minute motivational interviewing sessions) administered by a trained clinician will be at least 25% more effective than "standard care" (assessment/referral only) in decreasing drug use as measured by a 90-day Timeline Followback (6) (TLFB) calendar.
2. Test the effect of the brief intervention in increasing engagement in substance abuse treatment. We hypothesize that, among 12-18 year old patients who are referred to drug counseling or other treatments, the experimental intervention administered by a trained clinician will result in at least 25% more patients entering treatment compared to standard care, as measured by the numbers of patients who complete referrals to treatment providers.
3. Test the effect of the intervention on other substance-related outcomes. We hypothesize that the intervention will result in similar reductions in alcohol use, as measured by the TLFB, and in driving/riding while impaired (DRWI) risks as measured by the score of a 4-item self-reported scale. Other outcomes of interest include readiness to change, school performance, and experience of other harmful consequences of substance use and associated risk behaviors.
4. Identify factors that moderate and/or mediate the effect of the experimental intervention on our outcomes of interest (drug use, engagement in treatment), and estimate their effect sizes. Identifying moderating variables will help us to identify subgroups of optimal responders to the brief intervention. Based on our previous experience, we theorize that girls may respond more strongly to the intervention than boys, and that those who participate in other treatments (outpatient counseling) and/or a laboratory drug testing program will also have greater response.

Inclusion Criteria:

• 12-21 years old
• Use of alcohol, marijuana or other drugs 6 times in last 3 months
• CRAFFT score of 1 or greater
• Have completed evaluation at Adolescent Substance Abuse Program at Children's Hospital Boston

Exclusion Criteria:

• Can not read or understand English at a 6th grade reading level
• Needs immediate hospitalization