ArticleThe International journal on drug policy2020
International differences in patterns of cannabis use among adult cigarette smokers: Findings from the 2018 ITC Four Country Smoking and Vaping Survey.
Article in The International journal on drug policy, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 36 papers, 2 of them syntheses that pooled it.
What it found
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
36 citing papers in PubMed, 2 syntheses or guidelines pooled it, 49 citations in OpenAlex.
- Neuropsychological effects of cannabis use by continent and age: a systematic review.Frontiers in psychology · 2026Pooled it
- Associations of cannabis use, tobacco use, and incident anxiety, mood, and psychotic disorders: a systematic review and meta-analysis.Psychological medicine · 2024Pooled it
- Cannabis use among adults who smoke tobacco: Relations with switching from combusted cigarettes to e-cigarettes or very low nicotine cigarettes.Drug and alcohol dependence · 2025Trial
- A multi-site study examining the tobacco withdrawal trajectory in people with tobacco and cannabis co-use.Drug and alcohol dependence · 2025Trial
- CBClinical pharmacology and therapeutics · 2025Trial
- Determining the impact of cannabis use on tobacco cessation: Results from a prospective non-randomized tobacco treatment trial.Addiction (Abingdon, England) · 2026Article
- Changes in Cigarette Smoking Prevalence After Passing a Recreational Cannabis Legalization Law Without Retail Sales: Evidence From Virginia, U.S.AJPM focus · 2026Article
- Association between children's secondhand co-exposure to tobacco and cannabis smoke and elevated urinary cotinine levels: a cross-sectional analysis.BMJ public health · 2026Article
- Effects of Inhaled Tobacco and Cannabis Co-Use on Respiratory Health and Tobacco Cessation: An Official American Thoracic Society Research Statement.American journal of respiratory and critical care medicine · 2025Article
- Better health and less stress: an elicitation survey on quitting little cigars and cigarillos by young adults.BMC public health · 2025Article
- A preliminary investigation of tobacco co-use on endocannabinoid activity in people with cannabis use.Drug and alcohol dependence reports · 2025Article
- Nicotine-Cannabis Transitions and Nicotine Abstinence Among United States Adults.Epidemiology (Cambridge, Mass.) · 2025Article
- Article
- Associations of Cannabis Use, High-Risk Alcohol Use, and Depressive Symptomology with Motivation and Attempts to Quit Cigarette Smoking Among Adults: Findings from the 2020 ITC Four Country Smoking and Vaping Survey.International journal of mental health and addiction · 2025Article
- Perception of harm is strongly associated with complete ban on in-home cannabis smoking: a cross-sectional study.BMC public health · 2024Article
- Cannabis Use in Germany.Deutsches Arzteblatt international · 2024Observational
- Health, safety, and socioeconomic impacts of cannabis liberalization laws: An evidence and gap map.Campbell systematic reviews · 2023Article
- Pain is associated with exclusive use and co-use of tobacco and cannabis: Findings from Wave 5 (2018-2019) of the Population Assessment of Tobacco and Health Study.Addictive behaviors · 2023Article
- Understanding the complexity, patterns, and correlates of alcohol and other substance use among young people seeking help for mental ill-health.Social psychiatry and psychiatric epidemiology · 2023Article
- Co-use of cigarettes and cannabis among people with HIV: Results from a randomized controlled smoking cessation trial.Drug and alcohol dependence reports · 2023Article
Corrections and comments
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Authors and funding
19 authors at 8 institutions in 5 countries.
Funding
Abstract
backgroundAlthough evidence shows that co-use of cigarettes and cannabis is common, there is little research examining if co-use patterns vary depending on the regulatory environment for cannabis. This study examined patterns of co-use and perceptions of relative harm among cigarette smokers in four countries with different histories, and at different stages of cannabis legalization.
methodsData are from the 2018 International Tobacco Control 4CV Survey and included 10035 adult cigarette smokers from Canada, United States (US), Australia, and England. At the time of the survey, Canada and the US had relatively more permissive cannabis regulations compared to Australia and England.
resultsAmong this sample of 10035 cigarette smokers, Canada had the highest rate of cannabis co-use in the last 12 months (36.3%), followed by the US (29.1%), England (21.6%), and Australia (21.4%). Among past 12 month co-users (n = 3134), the US (40.2%) and Canada (35.2%) had the highest rates of daily cannabis use, followed by smokers in England (26.3%) and Australia (21.7%); Australian co-users had the highest rate of infrequent (<monthly) cannabis use. The highest proportion of co-users who smoked daily and used cannabis daily was in the US (34.8%), followed by Canada (30.6%), England (25.8%), and Australia (22.7%). More co-users in the US (78.3%) and Canada (73.6%) perceived smoked cannabis to be less harmful than cigarettes than in Australia (65.5%) and England (60.8%). The majority of co-users who used cannabis in the last 30 days had smoked it (92.3%), with those in England more likely to smoke cannabis (95.7%) compared to Canada (88.6%); there were no other differences between countries (US: 92.0%, Australia: 93.0%). Co-users in England (90.4%) and Australia (86.0%) were more likely to mix tobacco with cannabis than co-users in Canada (38.5%) and the US (22.3%).
conclusionPatterns of tobacco and cannabis co-use differed between countries. Smokers in Canada and the US had higher rates of co-use, daily cannabis use, dual-daily use of both cannabis and cigarettes, and were more likely to perceive smoked cannabis as less harmful than cigarettes compared to England and Australia. Further attention as to how varying cannabis regulations may impact co-use patterns is warranted.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.