Methodological biases in estimating the relationship between alcohol consumption and breast cancer: the role of drinker misclassification errors in meta-analytic results.

BACKGROUND: While alcohol consumption has been linked to breast cancer in women, few studies have controlled for possible biases created by including former or occasional drinkers in the abstainer reference group. We explored the potential for such misclassification errors as sources of bias in estimates of the alcohol-breast cancer relationship. METHODS: Meta-analyses of population case-control, hospital case-control, and cohort studies to examine relationships between level of alcohol use and breast cancer morbidity and/or mortality in groups of studies with and without different misclassification errors. RESULTS: Of 60 studies identified, only 6 were free of all misclassification errors. The abstainer reference group was biased by the inclusion of former drinkers in 49 studies, occasional drinkers (<10 g ethanol [EtOH] per week) in 22 and by both these groups in 18. Occasional drinkers were also mixed with light or hazardous-level drinkers in 22 studies. Unbiased estimates of the odds ratio (OR) for breast cancer were 1.011 (95% confidence interval [CI]: 0.891 to 1.148) among former drinkers (n = 11) and 1.034 (95% CI: 1.003 to 1.064) among occasional drinkers (n = 17). Hazardous-level drinking (>20 g < 41 g EtOH/d) was not significantly associated with breast cancer in studies with occasional drinker bias. However, in studies free from occasional drinker bias, the OR for breast cancer was 1.085 (95% CI: 1.015 to 1.160) for low-level (<21 g/d) drinkers (n = 17), 1.374 (95% CI: 1.319 to 1.431) for hazardous-level drinkers (n = 26), and 1.336 (95% CI: 1.228 to 1.454) for harmful-level (>40 g/d) drinkers (n = 9). CONCLUSIONS: While the great majority of studies of the alcohol-breast cancer link include misclassification errors, only misclassification of occasional drinkers was found to bias risk estimates significantly. Estimates based on error-free studies confirmed that low, hazardous and harmful levels of alcohol use each significantly increase the risk of breast cancer.

An assessment of federal alcohol policies in Canada and priority recommendations: Results from the 3rd Canadian Alcohol Policy Evaluation Project.

OBJECTIVE: To systematically assess the Canadian federal government's current alcohol policies in relation to public health best practices. METHODS: The 2022 Canadian Alcohol Policy Evaluation (CAPE) Project assessed federal alcohol policies across 10 domains. Policy domains were weighted according to evidence for their relative impact, including effectiveness and scope. A detailed scoring rubric of best practices was developed and externally reviewed by international experts. Policy data were collected between June and December 2022, using official legislation, government websites, and data sources identified from previous iterations of CAPE as sources. Contacts within relevant government departments provided any additional data sources, reviewed the accuracy and completeness of the data, and provided amendments as needed. Data were scored independently by members of the research team. Final policy scores were tabulated and presented as a weighted overall average score and as unweighted domain-specific scores. RESULTS: Compared to public health best practices, the federal government of Canada scored 37% overall. The three most impactful domains-(1) pricing and taxation, (2) marketing and advertising controls, and (3) impaired driving countermeasures-received some of the lowest scores (39%, 10%, and 40%, respectively). Domain-specific scores varied considerably from 0% for minimum legal age policies to 100% for controls on physical availability of alcohol. CONCLUSION: Many evidence-informed alcohol policies have not been adopted, or been adopted only partially, by the Canadian federal government. Urgent adoption of the recommended policies is needed to prevent and reduce the enormous health, social, and economic costs of alcohol use in Canada.

RéSUMé: OBJECTIF: Évaluer de manière systématique les politiques sur l'alcool actuelles du gouvernement fédéral canadien dans le cadre de pratiques de santé publique exemplaires. MéTHODES: Le projet de l'Évaluation des politiques canadiennes sur l'alcool 2022 a évalué les politiques fédérales sur l'alcool dans dix domaines. Ces domaines de politiques ont été pondérés en fonction de preuves sur leurs répercussions relatives, notamment leur efficacité et leur portée. Une échelle d'évaluation descriptive détaillée de pratiques exemplaires a été élaborée et examinée à l'externe. Entre juin et décembre 2022, des données sur les politiques ont été recueillies dans la législation officielle, sur des sites Web du gouvernement et au moyen de sources identifiées comme telles au cours des itérations précédentes du projet de l'Évaluation des politiques canadiennes sur l'alcool. Des personnes-ressources au sein des ministères concernés ont communiqué d'autres sources de données, examiné l'exactitude et le caractère exhaustif de ces données et apporté les modifications nécessaires. Les données ont été évaluées indépendamment par des membres de l'équipe de recherche. Les scores de politiques finaux ont été inscrits dans des tableaux et présentés sous forme d'une moyenne générale pondérée et de scores non pondérés par domaine. RéSULTATS: Comparativement aux pratiques de santé publique exemplaire, le gouvernement fédéral du Canada a obtenu un score général de 37 %. Les trois domaines susceptibles d'avoir les plus grandes répercussions, à savoir 1) la fixation des prix et la taxation, 2) le contrôle du marketing et de la publicité, et 3) les mesures contre la conduite avec facultés affaiblies, se sont vu attribuer parmi les scores les plus bas (39 %, 10 %, et 40 % respectivement). Les scores par domaine variaient considérablement, allant de 0 % pour les politiques sur l'âge minimum légal à 100 % pour le contrôle de la disponibilité physique de l'alcool. CONCLUSION: De nombreuses politiques sur l'alcool reposant sur des preuves n'ont pas été adoptées, ou l'ont été seulement partiellement, par le gouvernement fédéral canadien. Il est urgent d'appliquer les politiques recommandées pour prévenir et réduire les énormes coûts sanitaires, sociaux et économiques de la consommation d'alcool au Canada.

A systematic review and meta-analysis of alcohol consumption and injury risk as a function of study design and recall period.

BACKGROUND: It is well established that alcohol consumption is associated with an increased risk of injury. This systematic review and meta-analysis addresses important methodological issues commonly encountered in the alcohol and injury field by delineating the effect of study design and alcohol consumption recall period on effect size magnitude and by conducting gender-specific analyses. METHODS: We performed meta-analyses using random-effect models. Data sources were peer-reviewed studies on alcohol and injury from 1970 to 2009 from MEDLINE, PsychInfo, and on-line journals. Case-control or case-crossover emergency department (ED) studies reporting injury risk from alcohol consumption 6 hours before injury were included. RESULTS: The overall odds of injury were 2.799 (2.214 to 3.538, p < 0.001). For case-crossover studies, the odds were 3.815 (2.646 to 5.499, p < 0.001); for ED case-control studies, the odds were 1.977 (1.385 to 2.821, p < 0.001); and for population case-control designs, the odds were 3.145 (1.583 to 6.247, p < 0.005). The "usual frequency" recall period yielded an odds ratio of 4.235 (2.541 to 7.057, p < 0.001), compared to 2.320 (1.789 to 3.008, p < 0.001) for all other methods. There were significant differences in odds ratio magnitude when comparing studies by design and recall period. Females had higher odds of injury than males, 2.285 (1.361 to 3.836, p < 0.005) versus 1.071 (0.715 to 1.605, p = 0.737). CONCLUSIONS: Study design and alcohol consumption recall period have significant effects on effect size magnitude in estimating the risk of injury from alcohol consumption 6 hours prior to injury. For the "usual frequency" case-crossover design, significant moderator effects were found, resulting in overestimates of injury risk from alcohol. ED case-crossover designs tend to overestimate risk, and ED case-control designs tend to underestimate. We provide recommendations for future ED research.