Single-Item Measure Helps Providers Screen for Cannabis Use Disorder
What’s the Question?
Nearly 50 million people in the U.S. use cannabis and use is increasing. Frequent cannabis use intensifies the risk for developing cannabis use disorder (CUD), a behavioral health condition in which someone continues to use cannabis despite significant impairment and distress. CUD can impact as many as 5-14% of young adults and 8-23% of people with mental health or other substance use disorders but is underrecognized in medical settings and largely goes untreated.
A brief, valid cannabis screen could help increase identification of CUD, but for it to be useful, it has to be easy and fast for medical providers to use. Would a single-item measure provide enough information to screen for cannabis use disorder?
This study aimed to find out, testing the use of the Single-Item Screen-Cannabis (SIS-C) when documented in the electronic health record (EHR) as part of routine care. The SIS-C asks “How often in the past year did you use marijuana?” with response options never, less than monthly, monthly, weekly, daily or almost daily.
How Was This Study Conducted?
Adult patients aged 18 or older at Kaiser Permanente in Washington State who completed the SIS-C in primary care settings in 2019 were asked if they wanted to participate in a confidential cannabis survey.
In total, 1688 primary care patients completed the survey, which consisted of the more substantial CUD measure the Composite International Diagnostic Interview Substance Abuse Module (CIDI-SAM). By comparing scores on the CIDI-SAM with patient responses to the SIS-C in their previous appointments, researchers could figure out whether the SIS-C worked well at screening patients for CUD.
What Did Researchers Find Out?
Among the participants, 6.6% met criteria for past-year CUD based on the CIDI-SAM – this is slightly higher than national samples.
Researchers found that report of any past year cannabis use on the SIS-C was predictive of any level of CUD on the CIDI-SAM, suggesting that providers whose patients report any cannabis use should follow-up with additional assessment. Reports of monthly or more frequent use of cannabis on the SIS-C were predictive of “moderate to severe” CUD, suggesting that providers whose patients report these levels of use may want to engage in more intensive intervention.
However, while the SIS-C was found to be easy to use and effective, it also had a high rate of false positives -- in the study population, predictive values of a positive screen ranged from 17% to 34%, while predictive values of a negative screen ranged from 97% to 100%. That means that the SIS-C is better at identifying patients without CUD, and patients who screen positive on the SIS-C need to receive additional assessment to truly determine whether or not they have cannabis use disorder.
What are the Implications for the Workforce?
Cannabis use is prevalent and increasing, and frequent use increases the risk of CUD. The use of a validated single-item cannabis screen like the SIS-C could help providers more readily determine which patients need additional assessment and/or care for problematic use.