Machine learning applications in tobacco research: a scoping review.

OBJECTIVE: Identify and review the body of tobacco research literature that self-identified as using machine learning (ML) in the analysis. DATA SOURCES: MEDLINE, EMABSE, PubMed, CINAHL Plus, APA PsycINFO and IEEE Xplore databases were searched up to September 2020. Studies were restricted to peer-reviewed, English-language journal articles, dissertations and conference papers comprising an empirical analysis where ML was identified to be the method used to examine human experience of tobacco. Studies of genomics and diagnostic imaging were excluded. STUDY SELECTION: Two reviewers independently screened the titles and abstracts. The reference list of articles was also searched. In an iterative process, eligible studies were classified into domains based on their objectives and types of data used in the analysis. DATA EXTRACTION: Using data charting forms, two reviewers independently extracted data from all studies. A narrative synthesis method was used to describe findings from each domain such as study design, objective, ML classes/algorithms, knowledge users and the presence of a data sharing statement. Trends of publication were visually depicted. DATA SYNTHESIS: 74 studies were grouped into four domains: ML-powered technology to assist smoking cessation (n=22); content analysis of tobacco on social media (n=32); smoker status classification from narrative clinical texts (n=6) and tobacco-related outcome prediction using administrative, survey or clinical trial data (n=14). Implications of these studies and future directions for ML researchers in tobacco control were discussed. CONCLUSIONS: ML represents a powerful tool that could advance the research and policy decision-making of tobacco control. Further opportunities should be explored.

Is blue the new green? Repackaging menthol cigarettes in response to a flavour ban in Ontario, Canada.

BACKGROUND: As of 1 January 2017, the Canadian province of Ontario banned the distribution and sale of menthol tobacco products. There is limited knowledge about how tobacco companies will adapt their packaging in response to a menthol ban. METHODS: We conducted a content analysis of preban traditional menthol (no capsule) and menthol capsule cigarette packs and their postban replacements. Preban and postban packs were matched using tobacco company descriptions of replacement brands in business-to-business marketing materials, advertising on cigarette pack cellophane and a tobacco company website. RESULTS: A total of 63 menthol (n=30) and 'non-menthol alternative' (n=33) cigarette packs were included in the analysis. Approximately half of the preban packs were menthol capsule cigarettes and half traditional menthol cigarettes. While some postban brands continued to convey menthol-like qualities via the colour and/or brand descriptor 'green', 'blue' was the most common colour and brand descriptor postban. Packs shifted from using 'menthol' and/or 'fresh' as taste descriptor preban to using 'smooth' postban; some postban packs had 'non-menthol alternative' or 'without menthol/capsules' written on their cellophane. The presence of innovative filter technologies continued in the postban samples. CONCLUSION: Results suggest that tobacco companies attempted to maintain menthol smokers in Ontario by aggressive preban promotion of menthol capsule cigarettes, continued promotion of innovative filter technologies and by directing smokers to non-menthol alternatives whose packaging both in text and in colour connoted menthol-like qualities (eg, green) and reduced harshness or harm (eg, blue, white, silver, smooth taste).

Impacts of Canada's minimum age for tobacco sales (MATS) laws on youth smoking behaviour, 2000-2014.

BACKGROUND: Recently, the US Institute of Medicine has proposed that raising the minimum age for tobacco purchasing/sales to 21 years would likely lead to reductions in smoking behavior among young people. Surprisingly few studies, however, have assessed the potential impacts of minimum-age tobacco restrictions on youth smoking. OBJECTIVE: To estimate the impacts of Canadian minimum age for tobacco sales (MATS) laws on youth smoking behaviour. DESIGN: A regression-discontinuity design, using seven merged cycles of the Canadian Community Health Survey, 2000-2014. PARTICIPANTS: Survey respondents aged 14-22 years (n=98 320). EXPOSURE: Current Canadian MATS laws are 18 years in Alberta, Saskatchewan, Manitoba, Quebec, the Yukon and Northwest Territories, and 19 years of age in the rest of the country. MAIN OUTCOMES: Current, occasional and daily smoking status; smoking frequency and intensity; and average monthly cigarette consumption. RESULTS: In comparison to age groups slightly younger than the MATS, those just older had significant and abrupt increases immediately after the MATS in the prevalence of current smokers (absolute increase: 2.71%; 95% CI 0.70% to 4.80%; P=0.009) and daily smokers (absolute increase: 2.43%; 95% CI 0.74% to 4.12%; P=0.005). Average past-month cigarette consumption within age groups increased immediately following the MATS by 18% (95% CI 3% to 39%; P=0.02). There was no evidence of significant increases in smoking intensity for daily or occasional smokers after release from MATS restrictions. CONCLUSION: The study provides relevant evidence supporting the effectiveness of Canadian MATS laws for limiting smoking among tobacco-restricted youth.