Measuring change in cannabis use

Abstract

We examined the ability of the Cannabis User Disorders Identification Test – Revised (CUDIT-R) to detect change in a treatment sample, including correlation with changes in other clinically relevant areas of functioning, and to determine reliable and clinically significant change thresholds. 133 cannabis-using patients taking part in a treatment trial for concurrent substance use and mood disorder were administered the 8-item CUDIT-R at baseline, 6 and 12 months, in addition to assessment of current cannabis use disorder, mood, alcohol use, motivation and employment status. Significant reductions in CUDIT-R scores were observed and were correlated with change in cannabis diagnosis, and improvement in mood. Higher motivation at baseline predicted greater reduction in CUDIT-R score. Reliable change was identified as occurring when CUDIT-R score changed by two or more, while clinically significant change, benchmarked against an increase or decrease of one DSM-IV cannabis dependence symptom, was equated to a CUDIT-R score changing by 3 or more points.

• Cannabis
• improvement
• measurement
• outcome

Declaration of interest

The authors report no conflict of interest. The authors alone are responsible for the content and writing of this article. The SHADE study was funded by the Alcohol Education Rehabilitation Foundation (AERF, Grant Number: AERFDOCS\2002\G0353).