Development and evaluation of the Marijuana Reduction Strategies Self-Efficacy Scale.

To evaluate several psychometric properties of a questionnaire designed to assess college students' self-efficacy to employ 21 cognitive-behavioral strategies intended to reduce the amount and/or frequency with which they consume marijuana, we recruited 273 marijuana-using students to rate their confidence that they could employ each of the strategies. Examination of frequency counts for each item, principal components analysis, internal consistency reliability, and mean interitem correlation supported retaining all 21 items in a single scale. In support of criterion validity, marijuana use-reduction self-efficacy scores were significantly positively correlated with cross-situational confidence to abstain from marijuana, and significantly negatively correlated with quantity and frequency of marijuana use and marijuana-related problems. In addition, compared with respondents whose use of marijuana either increased or remained stable, self-efficacy was significantly higher among those who had decreased their use of marijuana over the past year. This relatively short and easily administered questionnaire could be used to identify college students who have low self-efficacy to employ specific marijuana reduction strategies and as an outcome measure to evaluate educational and skill-training interventions.

Psychometric evaluation of the Marijuana Reduction Strategies Self-Efficacy Scale with young recreational marijuana users.

INTRODUCTION: This study evaluated the cue-reactivity and several psychometric properties of a questionnaire designed to assess marijuana users' self-efficacy to employ 21 specific cognitive-behavioral strategies to reduce their marijuana use. METHOD: Using a web-based recruitment and data-collection procedure, 513 regular marijuana users completed dependent measures following marijuana-related or control cue exposure. RESULTS: Although exposure to marijuana-related stimuli significantly increased reported craving, mean reduction-strategy self-efficacy scores did not differ as a function of cue exposure. Reliability analyses supported retaining all 21 items as a single scale. Reduction-strategy self-efficacy was positively associated with marijuana-refusal self-efficacy and with recent past use of reduction strategies, was negatively associated with quantity and frequency of marijuana use and marijuana-related problems, and was positively but weakly associated with general self-efficacy. The most frequently reported strategies that were employed reflected restricting marijuana use to once per day, not keeping a large stash available, turning down unwanted hits, and not obtaining more marijuana right away if one's supply runs out. CONCLUSIONS: These findings further support the reliability and validity of the questionnaire when administered to a diverse sample of regular marijuana users.