Dissertation Defence: Multidimensional Assessment of Cannabis Use: Development and Validation of the Brief Composite Cannabis Assessment Tool (BCCAT)
July 30 at 10:00 am - 2:00 pm
Tashia Petker, supervised by Dr. Zach Walsh, will defend their dissertation titled “Multidimensional Assessment of Cannabis Use: Development and Validation of the Brief Composite Cannabis Assessment Tool (BCCAT)” in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Psychology – Clinical Psychology.
An abstract for Tashia Petker’s dissertation is included below.
Examinations are open to all members of the campus community as well as the general public. Registration is not required for in-person exams.
Abstract
Background: shifts in public opinion and legislation regarding medical and recreational cannabis use have motivated researchers and clinicians to gain a comprehensive understanding of the diverse aspects of cannabis use. Established measures of cannabis use tend to focus on singular dimensions, and fail to capture therapeutic cannabis use and harm reduction motives. This dissertation was undertaken with the aims of filling this gap in cannabis use assessment with a short, multidimensional measure: the Brief Composite Cannabis Assessment Tool (BCCAT).
Methods: A preliminary set of 25 candidate items was generated and tested in a sample of 397 adults. Factor analysis and content evaluation informed dimension reduction to a set of 12 items comprising the BCCAT with subscales for Therapeutic Use, Problematic Use, and Recreational Use. A composite score, the Relative Benefit Index, was introduced as an estimate of overall positive impact. The psychometric properties of the BCCAT were examined in 437 nonmedical users, 2032 medical cannabis patients, and 308 people who use drugs. Construct validity was examined by comparing correlations between BCCAT subscales and established measures of cannabis use motives and problematic use and by examining group differences in BCCAT profiles using analysis of variance. Reliability was estimated by internal consistency analysis.
Results: Factor analysis of the 25-item candidate set and examination of the scree plot resulted in a three factor solution reflecting the dimensions of Therapeutic Use, Recreational Use, and Problematic Use. Items with factor loadings greater than 0.298 were considered for inclusion, with a total of four items per subscale selected, for a total of 12 items comprising the BCCAT. Across the four samples reliability estimates ranged from less than optimal to excellent. The BCCAT subscales were found to have good convergent and discriminant validity, and multidimensional profiles demonstrated distinct patterns based on primary use motives.
Conclusions: The BCCAT comprehensively evaluates cannabis use by capturing therapeutic, recreational, and problematic use patterns in one brief questionnaire. It distinguishes use patterns across populations without overemphasis on pathology, and can be applied to support harm reduction and compassionate clinical care.
