ArticleCMAJ open2018
Cannabis use among middle and high school students in Ontario: a school-based cross-sectional study.
Article in CMAJ open, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
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Who cites it
9 citing papers in PubMed.
- 2025 update of the Greig Health Record: Part 2-what's controversial?Canadian family physician Medecin de famille canadien · 2026Review
- Identifying Stigma Phenotypes in Social Media Narratives of Substance Use: Observational Study.Journal of medical Internet research · 2025Observational
- Cannabis use in adolescence and young adulthood and its effects on brain structure and function: a scoping review.Frontiers in psychiatry · 2025Review
- Understanding the epidemiology and perceived efficacy of cannabis use in patients with chronic musculoskeletal pain.Journal of cannabis research · 2024Article
- Nicotine and Nicotine-Free Vaping Behavior among a Sample of Canadian High School Students: A Cross-Sectional Study.Children (Basel, Switzerland) · 2023Article
- Cannabis use and associated factors among 15-16-year-old adolescents in Estonia 2003-2019: Results from cross-sectional ESPAD surveys.Nordisk alkohol- & narkotikatidskrift : NAT · 2021Article
- Alcohol Consumption Among Spanish Female Adolescents: Related Factors and National Trends 2006-2014.International journal of environmental research and public health · 2019Article
- An examination of how age of onset for alcohol, cannabis, and tobacco are associated with physical activity, screen time and BMI as students are preparing to graduate from high school.Preventive medicine reports · 2019Article
- Relationships between Problematic Cannabis Use and Risky Behaviors in Spanish Adolescents.International journal of environmental research and public health · 2019Article
Corrections and comments
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Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundCannabis use can have serious detrimental effects in children and adolescents. It is therefore important to continually assess the use of cannabis among young people in order to inform prevention efforts. We assessed the prevalence of cannabis use among middle and high school students in Ontario and examined its association with demographic and behavioural factors.
methodsData were obtained from the 2015 Ontario Student Drug Use and Health Survey, a province-wide school-based survey of students in grades 7 through 12. Analyses included a representative sample of 9920 middle and high school students. Bivariate cross-tabulations and logistic regression analyses were used to investigate the factors associated with cannabis use.
resultsOverall, 21.5% and 13.9% of students reported using cannabis in the previous year and previous month, respectively. The conditional probability that an adolescent who reported cannabis use in the previous year would report daily use was 12.5%. There was a significant dose-response gradient with age, with older students being more likely to use cannabis than younger students. In multivariable analyses, being in grades 10 through 12 (odds ratios [ORs] ranged from 3.71 to 3.85), being black (OR 2.67 [95% confidence interval (CI) 1.76-4.05]), using tobacco cigarettes (OR 10.10 [95% CI 8.68-13.92]) and being an occasional (OR 5.35 [95% CI 4.01-7.13]) or regular (OR 14.6 [95% CI 10.8-19.89]) alcohol user were associated with greater odds of cannabis use. Being an immigrant was associated with lower odds of cannabis use (OR 0.55 [95% CI 0.39-0.78]).
interpretationThe findings suggest that cannabis use is prevalent among middle and high school students in Ontario and is strongly associated with tobacco cigarette smoking and alcohol consumption. Future research should document trends in cannabis use over time, including its risks, especially when the legalization of recreational cannabis comes into effect.
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Registered trials
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