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Associations of cannabis use frequency and cannabis use disorder with receiving a substance use screen and healthcare professional discussion of substance use.


Published in: The American Journal on Addictions

By: Moore, DiNitto, & Choi. 2021



The aim of this study was to assess the relationship between frequency of cannabis use, and cannabis use disorder (CUD), and the rate of screening and brief intervention (SBI) by a health professional.



The investigators scrutinized data from a nationally representative survey of drug use and health (NSDUH), in the United States from 2015-2019, in which over 200,000 individuals aged over 18 years participated voluntarily. From that set of responses, 36,374 participants reported having both used cannabis, and accessed a primary healthcare setting in the previous 12-months. Participants were then groups based on their frequency of cannabis use in the past year (1-11 days, 12-49 days, 50-99 days, 100-199 days, 200-299 days, 300+ days), as well as the presence of a diagnosis of CUD. Statistical methods were then used to assess relationships between CUD, cannabis frequency and receipt of SBI practices, and a number of other variable factors.



The investigators found some interesting findings about the likelihood of receiving screening only, SBI, and BI only, using logistic regression analyses. First, in terms of likelihood of being screened for drug use, those who reported higher frequency of use tended to be screened more. Specifically, researchers found that the odds of receiving a drug screen were 27% higher for those using cannabis on 300+ days, compared with those using cannabis 1-11 days per year (OR: 1.27, 95 CI: 1.14, 1.41). Similarly, those reporting 200-299 days of cannabis use per year displayed 20% increased odds of receiving a drug screen compared with 1-11 days of use. Lower, but non-significant odds were found for each of the remaining groups. These findings suggest that more frequent users are more likely to be screened for CUD.

Among those who received a screen, the likelihood of also then receiving a BI was more pronounced. Across all groups, the likelihood of receiving BI among those screened were significantly higher (at rate increases ranging from 40% [50-99 days] and 83% [300+ days]) for those using cannabis more frequently compared with 1-11 days of use. However, interestingly, among those who did not receive a screen, compared to 1-11 days of use, those reporting 12-49 days of use were 2 times more likely to receive BI, and those reporting 300+ days were 2.4 times more likely. These findings suggest that, though there is a relationship between frequency of use and receipt of SBI, it appears that screening and brief intervention are seen as separate components.

The researchers also found associations those with CUD who were screened had a 22% increase in likelihood of receiving a BI (OR: 1.22, 95 CI: 1.08, 1.39). Interestingly, among those who were prescribed cannabis medically, those who were screened were 2.3 times more likely, and those who weren’t screened were 6.7 times more likely to receive BI than those using cannabis non-medically. Furthermore, females were 16% more likely to receive a screen, but subsequently 24% less likely to receive a BI compared to males. Reductions in likelihood of SBI were found in older participants, compared with those 18-25 years. Those more educated were more likely to receive both screening, and SBI. Finally, the researchers also found increased likelihood of SBI among those with mild, moderate and severe mental health disorders compared to those without. Other relationships between factors such as past year ambulatory care, past year hospitalization, AUD, Nicotine dependence and race were also explored. Overall, these findings suggest that SBI practices for cannabis use are occurring within primary healthcare settings which is encouraging. However the disaggregated nature of SBI approaches in this study, and the range of factors which influence whether an individual receives SBI are areas for improvement.



“Our findings that nonmedical users were less likely to receive a screen and discussion than medical users suggest SBIRT practices for nonmedical cannabis users need increased attention



The data in this research comes from a large, nationally representative sample which can be incredibly informative. This research demonstrates that SBI practices for cannabis are starting to be adopted more routinely. This study is also the first to address the need for screening and brief intervention among both medical and non-medical users of cannabis.



Overall, this research sheds important light on the practices of SBIRT for cannabis use among health professionals in the primary healthcare space. However, this research demonstrates that, although SBI practices are relatively common, there is a need for more standardized SBIRT approaches. Given that the ASSIST (and ASSIST-Lite) assesses risk primarily based on previous 3-month window, this presents an excellent opportunity for clinicians to re-administer the ASSIST at regular 3-month intervals. As we know, individual drug taking behaviours are dynamic and can change drastically across time, in response to other life events. Therefore it is useful to be reminded that screening and brief intervention can, and should, be conducted regularly in order to capture some of these changes. We have developed two smartphone apps – which allow participants to self-complete the ASSIST or the ASSIST-Lite and provide them with the option to download AND email their results in PDF format. This saves you valuable time during your consultation – time that could be better spent delivering a brief intervention and addressing other health complaints.


To download our smartphone apps (ASSIST Checkup and ASSIST Checkup Lite), visit the homepage of the ASSIST Portal where you will find the links to the iOS and Android stores


For more information and downloadable resources about the risks and harms of substance in general, as well as handy guidelines on screening and brief intervention, visit our Resources page


Here is a link to download our Cannabis Fact Sheet


You can read the full report here