Trends in substance use among US military personnel: the impact of changing demographic composition.

This paper examines the impact of the military population's changing demographic composition on observed changes in substance use by military personnel. Cross-sectional data are drawn from the six Department of Defense Worldwide Surveys of Substance Abuse and Health Behaviors Among Military Personnel conducted in 1980, 1982, 1985, 1988, 1992, and 1995. Using the method of direct standardization to adjust for changes in demographic composition, trends in substance use are examined. Changes in heavy alcohol use were more affected by demographic changes in the military population than were changes in illicit drug use or cigarette use. Findings indicate that changes in demographic composition may need to be controlled when assessing trends from cross-sectional surveys.