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I. Target Population

An important limitation of the NHSDA estimates of drug use prevalence is that they are only designed to describe the target population of the survey, the civilian noninstitutionalized population. Although this includes more than 98% of the total U.S. population, it does exclude some important and unique subpopulations who may have very different drug-using patterns. The survey excludes active military personnel, who have been shown to have significantly lower rates of illicit drug use. Persons living in institutional group quarters, such as prisons and residential drug treatment centers, are not covered in the NHSDA and have been shown in other surveys to have higher rates of illicit drug use. Also excluded are homeless persons not living in a shelter on the survey date, another population shown to have higher than average rates of illicit drug use. Appendix 3 describes other surveys that provide data for these populations.

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This page was last updated on June 16, 2008.