or depression” (AorD). Separate analyses were conducted for participants with the DEP phenotype—that is, with depression or depressive syndrome (which can occur in both alcoholics and nonalcoholics). The COGA researchers performed statistical analyses of differences in the prevalence of alcoholism and/or depression in various subgroups of study participants and tested interactions between variables. These data were calculated for all families of alcoholic probands and for control families where appropriate.
