Drug and Alcohol Dependence 2018;178:270-277. [doi: 10.1016/j.drugalcdep.2018.03.017]
Nathaniel L. Baker, MS, Kevin M. Gray, MD, Brian J. Sherman, PhD Kristen Morella, MPH, Gregory L. Sahlem, MD, Amanda M. Wagner, MA, Aimee L. McRae-Clark, PharmD (all from Medical University of South Carolina, SC Node).
The agreement between self-reported cannabis abstinence with urine cannabinoid concentrations in a clinical trials setting is not well characterized. This study assessed the agreement between various cannabinoid cutoffs and self-reported abstinence across three clinical trials, one including contingency management for abstinence. All three of the trials included both participant self-report and weekly urine samples for cannabis and creatinine concentration measurements. Bootstrapped data were assessed for agreement between self-reported 7+ day abstinence and urine cannabinoid tests using generalized linear mixed effects models for clustered binary outcomes. One study implemented contingency management for cannabis abstinence. Four hundred and seventy-three participants with 3787 valid urine specimens were included. Urine was analyzed for 11-nor-9-carboxy-delta-9-tetrahydrocannabinol and creatinine using immunoassay methods Biological cutoffs of 50, 100, and 200 ng/ml, as well as changes in CN normalized THCCOOH (25%/50% decrease), were assessed for agreement with self-reported abstinence during the three clinical trials.
Results found that agreement between measured THCCOOH and self-reported abstinence increases with increasing cutoff concentrations, while the agreement with self-reported non-abstinence decreases with increasing cutoff concentrations. Combining THCCOOH cutoffs with recent changes in CN-THCCOOH provides a better agreement in those self-reporting abstinence. Participants in the studies that received CM for abstinence had a lower agreement between self-reported abstinence and returned to use than those in studies that did not have a contingency management component.
Conclusions: Using a combination of both concurrent THCCOOH and recent changes in CN-THCCOOH, the agreement between self-reported cannabis abstinence initiation and measure agreemtn is shortened significantly. (Article (Peer-Reviewed), PDF, English, 2018)
Keywords: CTN platform/ancillary study | Data collection | Marijuana | Urinalysis | Drug and Alcohol Dependence (journal)
Document No: 1317, PMID: 29698894, PMCID: PMC5959795 (available 6/2019).
Submitted by Jack Blaine, CCTN, 7/23/2018.