CANDIS treatment program for cannabis use disorders: Findings from a randomized multi-site translational trial

Abstract Background In a recent paper, we reported the efficacy of a modular cognitive-behavioral intervention for treating adolescents and adults with cannabis use disorders (CUD). In this study, we examine the outcome of this intervention after translating it into clinical practice. Methods A multi-site, randomized controlled trial of 279 treatment seekers with ICD-10 cannabis use disorders aged 16– 63 years was conducted in 11 outpatient addiction treatment centers in Germany. Patients were randomly assigned to an Active Treatment (AT, n = 149) or Delayed Treatment Control (DTC, n = 130). Treatment consisted of 10 sessions of fully manualized individual psychotherapy that combined Cognitive-Behavioral Therapy, Motivational EnhancementTherapy and problem-solving training. Assessments were conducted at baseline, during each therapy session, at post-treatment and at three and six month follow-ups. Results At post assessment 53.3% of AT patients reported abstinence (46.3% negative urine screenings) compared to 22% of DTC patients (17.7% negative drug screenings) ( p < 0.001, Intention-to-treat analysis). AT patients improved in the frequency of cannabis use, number of cannabis dependence criteria, severity of dependence, as well as number and severity of cannabis-related problems. Effect sizes were moderate to high. While abstinence rates in the AT group decreased over the 3-month (negative urine screenings: 32.4%) and 6-month (negative urine screenings: 35.7%) follow-up periods, the effects in secondary outcomes were maintained. Conclusions The intervention can successfully be translated to and applied in clinical practice. It has the potential to improve access to evidence-based care for chronic CUD patients.