Background: Early substance use co-occurs with youths' self-organization into deviant peer groups in which substance use is central to social interaction. We hypothesized that the social dynamics of deviant peer groups amplify the risk of progressing from early use to later dependence, and that this influence occurs over and above escalations…

This report finds that adolescent smoking, drinking, misusing prescription drugs and using illegal drugs is, by any measure, a public health problem of epidemic proportion, presenting clear and present danger to millions of America's teenagers and severe and expensive long-range consequences for the entire population. This report is a wake-up call…