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COMPARING HAIR AND URINE ASSAYS FOR COCAINE AND MARIJUANA

NCJ Number
144741
Journal
Federal Probation Volume: 57 Issue: 2 Dated: (June 1993) Pages: 59-67
Author(s)
T Mieczkowski; R Newel
Date Published
1993
Length
9 pages
Annotation
This article reports the outcomes of hair assay, urinalysis, and self-reported cocaine and marijuana exposure for a sample of arrestees in the southeastern United States.
Abstract
Twice a year, the research group interviewed 250 to 300 male and female arrestees and collected hair and urine specimens at the booking stage of arrest. Four collection waves produced 1,245 cases for analysis. Hair samples were analyzed for cocaine, opiates, amphetamines, PCP, and marijuana. Urine specimens were analyzed for metabolites of cocaine, cannabinoids, opiates, and amphetamines. Findings demonstrated the effectiveness of hair specimens in identifying cocaine but not marijuana use. Arrestees tended to underreport cocaine use and overreport marijuana use. With respect to nonconcordant assay outcomes, arrestees were most likely to have a negative urinalysis for cocaine but a positive hair analysis. About 50 to 70 percent of those who were cocaine-positive denied any cocaine use within the last 2 months. More people tested urine-positive for marijuana than tested hair-positive, and more arrestees reported marijuana use than could be accounted for by either hair or urine assay. The authors note that hair assays will continue to be used by criminal justice and treatment professionals in drug testing because the technique offers several features not available with urinalysis. 55 references, 1 note, 4 tables, and 1 figure