Teenage sex, drugs and alcohol use: problems identifying the cause of risky behaviors.

The relationship between substance use and adolescent sexual activity is an important one, and extensive literature has shown that substance use is positively associated with adolescent sexual behaviors. While this is true, causality from substance use to risky sexual behaviors is difficult to establish, as it is likely that an adolescent's sexual behavior and substance use depend on a set of personal and social behaviors, many of which are unmeasured. Researchers must thus devise a credible empirical strategy in order to overcome this omitted variable bias. Using the first waves of the National Longitudinal Survey of Adolescent Health and the 1997 National Longitudinal Survey of Youth, we call into question recent methods used to determine causality. Despite attempts to determine the causal relationship between substance use and sexual behavior, the nature of the relationship remains unknown. Copyright 2004 Elsevier B.V.