... present use, and the more methodologically sophisticated the study, and the greater the reliability and validity of itsmeasures, the more accurate are the prevalence estimates. These data cannot, ... ways by the study sites, the sources of the sample and sample selection methods, and the measures used to assessalcohol and other drug use.Until recently, information about the extent of the alcohol ... stable, and these changes were most typically towardsreduced use.Information from the ECA and other cross-sectional studies and that from the Normative Aging and other longitudinal studies nonetheless...