title: The impact of alcohol misclassification on the relationship between alcohol and pregnancy outcome.
abstract: Underreporting, more than overreporting, is a problem in studies of the effects of alcohol consumption using self-reported data. Numerical examples illustrate that in studies of the effect of alcohol, nondifferential misclassification of alcohol consumption due to underreporting may lead to a bias away from the null value. It may also cause a true threshold level for alcohol to appear as a dose-response relationship. It is shown that the effect of misclassification on effect estimates will depend on the true frequency of abstainers in the studied population.
authors.forename: P H
authors.initials: PH
authors.lastname: Verkerk
mesh_terms: D000428:Alcohol Drinking / Q000453:epidemiology*; D015982:Bias; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D013695:Temperance