Epidemiology of drug abuse in the United States: a summary of methods and findings.

Epidemiology has recently been used to effectively track and analyze drug abuse patterns. This article generally describes methods used in the United States for estimating and monitoring drug abuse. It outlines the advantages and limitations of such data sources as surveys, indicators, and ethnography, and briefly explores the work and utility of local, national, and international drug surveillance networks. In addition, it describes national and local patterns of heroin, cocaine, and marijuana abuse.