Methodological Biases in Estimating the Relationship Between Alcohol Consumption and Breast Cancer: The Role of Drinker Misclassification Errors in Meta‐Analytic Results

摘要: 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 the abstainer reference group. We explored potential such misclassification errors as sources of bias estimates alcohol–breast relationship. Methods Meta-analyses population case–control, hospital and cohort examine relationships between level use morbidity and/or mortality groups with without different errors. Results Of 60 identified, only 6 were free all errors. The group was biased inclusion 49 studies, ( 20 g  40 g/d) (n = 9). Conclusions While great majority link include errors, found risk significantly. Estimates based on error-free confirmed that low, hazardous harmful levels each significantly increase cancer.