Adolescents were asked whether they had seen either of their parents drunk. Five response categories were possible, ranging from "never" to "a few times a week". It was not possible to distinguish between having seen the mother or father drunk. Sibling correlations show high reliability: The polychoric correlation was 0.57 in 1483 pairs of siblings and 0.68 in 96 pairs with less than one year of age difference.
