Featured article A randomized controlled trial of brief cognitive–behavioral interventions for cannabis use disorder Jan Copeland Ph.D. a, *, Wendy Swift Ph.D. a , Roger Roffman Ph.D. b , Robert Stephens Ph.D. c a National Drug and Alcohol Research Centre, University of New South Wales, Sydney 2052, Australia b School of Social Work, University of Washington, Seattle, WA 98195, USA c Department of Psychology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0436, USA Received 16 January 2001; accepted 2 March 2001 Abstract The increasing demand for treatment for cannabis dependence in Australia and internationally has led to the identification of significant gaps in knowledge of effective interventions. A randomized controlled trial of brief cognitive – behavioral interventions (CBT) for cannabis dependence was undertaken to address this issue. A total of 229 participants were assessed and randomly assigned to either a six-session CBT program (6CBT), a single-session CBT intervention (1CBT), or a delayed-treatment control (DTC) group. Participants were assisted in acquiring skills to promote cannabis cessation and maintenance of abstinence. Participants were followed-up a median of 237 days after last attendance. Participants in the treatment groups reported better treatment outcomes than the DTC group. They were more likely to report abstinence, were significantly less concerned about their control over cannabis use, and reported significantly fewer cannabis-related problems than those in the DTC group. Those in the 6CBT group also reported more significantly reduced levels of cannabis consumption than the DTC group. While the therapist variable had no effect on any outcome, a secondary analysis of the 6CBT and 1CBT groups showed that treatment compliance was significantly associated with decreased dependence and cannabis-related problems. This study supports the attractiveness and effectiveness of individual CBT interventions for cannabis use disorders and the need for multisite replication trials. D 2001 Elsevier Science Inc. All rights reserved. Keywords: Marijuana; Dependence; Treatment; Outcome; RCT 1. Introduction Cannabis is by far the most common illicit drug of dependence in English-speaking countries (Hall, Teesson, Lynskey, & Degenhardt, 1999). The Australian National Survey of Mental Health and Well-being reported that among those using cannabis on at least five occasions in the previous year, 23.3% met ICD-10 criteria for a current cannabis use disorder (Hall, Teesson, Lynskey, & Degen- hardt, 1998). These Australian rates of current cannabis disorder are even higher than the U.S. National Comorbidity Study, which found that 9.2% of those who reported any lifetime use of cannabis developed dependence as measured by DSM-III-R criteria (Anthony, Warner, & Kessler, 1994). Along with the growing recognition of the range of potential cannabis-related harms (Kalant, Corrigall, Hall, & Smart, 1999), there is an increasing demand for treatment (SAMHSA, 1999; Torres, Mattik, Chen, & Bailie, 1995). While there has been a range of therapies applied to the treatment of drug dependence, there has been a paucity of clinical research into the assessment of cannabis use dis- orders, and little systematic development of cannabis-spe- cific interventions (Budney, Radonovich, Higgins, & Wong, 1998). Most interventions used for cannabis dependence have been adaptations of alcohol interventions (e.g., Miller and Gold, 1989; Zweben and O’Connell, 1992). The 12-step fellowship movements, including Alcoholics Anonymous and Narcotics Anonymous, have also been used by cannabis clients seeking assistance. Marijuana Anonymous is a developing program in the U.S. but has not been established successfully in Australia. Furthermore, the efficacy of 12- step interventions remains unproven. There has been one small trial of a cannabis intervention using aversion therapy (Smith, Schmeling, & Knowles, 1988), but its efficacy has not been established. 0740-5472/01/$ – see front matter D 2001 Elsevier Science Inc. All rights reserved. PII:S0740-5472(01)00179-9 * Corresponding author. Tel.: +61-2-9385-3472; fax: +61-2-9385-3468. E-mail address: J.Copeland@unsw.edu.au (J. Copeland). Journal of Substance Abuse Treatment 21 (2001) 55 – 64