Little is known about how adolescents' peer relations might alter whether sport participation is associated with alcohol use. Consistent with social learning theory, we found that sport participation was protective against alcohol use if these peers had low alcohol use, but athletes were likely to use alcohol if their sport friends and teammates…

A gender gap in alcohol and drug use exists but is somewhat smaller than the gender gap in other forms of delinquency. This article extends studies that examine the gender-delinquency relationship to substance use in particular and estimate the extent to which major risk and protective factors mediate the association between gender and alcohol and…

Analyzing problem-behavior trajectories can be difficult. The data are generally categorical and often quite skewed, violating distributional assumptions of standard normal-theory statistical models. In this article, the authors present several currently available modeling options, all of which make appropriate distributional assumptions for the…

The Monitoring the Future (MTF) study involves an ongoing series of national surveys of American adolescents and adults that has provided the nation with a vital window into the important, but largely hidden, problem behaviors of illegal drug use, alcohol use, tobacco use, anabolic steroid use, and psychotherapeutic drug use. For more than a third…

Monitoring the Future (MTF), which is now in its 36th year, is a research program conducted at the University of Michigan's Institute for Social Research under a series of investigator-initiated research grants from the National Institute on Drug Abuse. The study is comprised of several ongoing series of annual surveys of nationally representative…