Abstract
Using urine test results as a gold standard, this report evaluates the validity of illicit drug use reports for five illicit substances provided in a multisite, national interview study of juvenile arrestees. Willingness to report substance use varied according to the type of substance, the time frame for substance use reports, and the characteristics of the juveniles asked to provide the reports. Youth were particularly reluctant to disclose recent use of cocaine and heroin. Race/ethnicity and willingness to disclose other substance use were the most important predictors of cocaine use disclosure among those testing positive for this drug. Race/ethnicity differences in validity were evaluated in the context of other recent epidemiological findings from surveys of drug use in the United States. Implications for the measurement of drug use in criminal justice samples are discussed.