Assessing the Efficacy of MOTI-4 for Reducing the Use of Cannabis Among Youth in the Netherlands: A Randomized Controlled Trial

The Moti-4 intervention, in which motivational interviewing, self-monitoring, and strengthening behavioral control are used, was developed in the Netherlands in response to several rapid assessments of problematic use of cannabis among vulnerable adolescents. The main goal of the study reported in this article was to determine whether the Moti-4 intervention was able to reduce two outcome measures pertaining to the level of cannabis use; the amount of Euros spent a week on cannabis and the mean number of cannabis joints (cigarettes) smoked in a week.In a randomized controlled trial (RCT) with a 6-month follow-up, 27 trained Dutch prevention workers recruited 71 Moti-4 participants and 60 controls assigned to usual care. Participants were Dutch youth aged 14-24 years who had used cannabis during the preceding month. At baseline (T0), post-test (T1) and 6-month follow-up (T2), participants completed a questionnaire with 51 items. The 27 prevention workers also completed a checklist to assess the fidelity of delivering each item to each participant in the Moti-4 protocol. Multilevel and binary logistic regression was used to assess the impact of the prevention worker and 14 participant variables on the likelihood of drop-out. Mean scores for cannabis use outcome measures by Moti-4 participants and controls at baseline, T1 and T2 were compared using paired sample t-tests. Top-down multiple regression was used to assess relationships between Moti-4 and 13 other variables on the one hand and changes in weekly cannabis use at T1 and T2 on the other. The Moti-4 experimental condition had a significant and positive influence in reducing the level of expenditure on cannabis (p < 0.05). There was no significant difference in outcome, neither for the 4 participating institutes nor for the professionals implementing the intervention. Baseline cannabis use was the strongest predictor (p < 0.001) of weekly cannabis expenditure at posttest and 6-month follow-up. This effect was still present at T2. Being female, having two Dutch parents and perceived behavioral control also made significant positive contributions (p < 0.05). Attitude at baseline was only related to cannabis expenditure after 6 months (p = 0.005). At T2 Moti-4 participants were found to have a significant reduction in the number of joints smoked weekly compared to T0 (on the average 4 joints). The study demonstrated that Moti-4 is an effective intervention to reduce cannabis use in youth

Developing the Moti-4 intervention, assessing its feasibility and pilot testing its effectiveness

Background: The Moti-4 intervention was developed to prevent addiction and other health problems among vulnerable adolescent cannabis users. The aims of Moti-4 are to reduce the use of cannabis among adolescents and to encourage their motivation to change their behavior. Methods: Intervention Mapping, a systematic approach to developing theory- and evidence-based interventions, was used to develop a protocol for the intervention. The process of developing the intervention also used the method of responsive evaluation to explore the opinions of the immediate target group and intermediaries (N = 31). Feasibility was assessed in 9 interviews and analyzed in grids. A quantitative pilot analysis involving a pre- and post-assessment in 31 subjects assessed whether the intervention was able to reduce drug use and would change intentions to change drug use behavior. Results: Using Intervention Mapping resulted in the development of a substantial four-session intervention with a clear manual and training for prevention workers. The choice of 12 consecutive steps was based on the Trans Theoretical Model of Behavior Change, Motivational Interviewing, Theory of Planned Behavior and the Self Determination Theory. Positive aspects of working with Moti-4 were assessed in a feasibility study. Criticism by users has led to improvements to the manual. In the pilot study, the average weekly amount spent on cannabis decreased significantly from an average €17.77 to €11,95 in the period after the intervention, with a medium effect size (d = 0.36). Likewise, a significant decrease was found in the frequency of use during the past week, from 4.3 to 2.4 (d = .52). As to motivation to change, a statistically significant increase was found in planning (d = .44) and a large increase in the desire to stop (d = .76). The change in the motivation to smoke less cannabis was small. Conclusion: Intervention Mapping proved to be a useful approach for the development of the intervention, using a productive combination of theory and community knowledge. The pre- and post-test pilot study showed that the intervention generally brought about a considerable positive change in the two principle targets, cannabis use and motivation. There is a need for further (controlled) research into its effectiveness and implementation as a standard method in addiction prevention services