NCJ Number
129292
Date Published
1991
Length
5 pages
Annotation
This is a report on a study that compared the effectiveness of four commonly used urine testing technologies.
Abstract
The urine testing technologies examined were EMIT, TDx FPIA, Abuscreen RIA, and standard thin-layer chromatography (TLC). Testing results were compared against gas chromatography/mass spectrometry, the most accurate method of drug detection. A total of 2,668 urine specimens from parolees and arrestees were examined. Each sample was screened for opiates, cocaine, phencyclidine, and marijuana. Test results showed a clear difference between the accuracy of the immunoassays as a group -- EMIT, TDx, and RIA -- and thin-layer chromatography. Standard TLC performed poorly in identifying the presence of illegal drugs. TLC identified only 8 to 19 percent of the specimens containing opiates, cocaine, amphetamines, and PCP and only 48 percent of the specimens that contained marijuana. Among the immunoassays, no one type of testing procedure was consistently superior in the identification of positive and negative urine specimens for the five drugs. Study results indicate that the two immunoassay technologies conducted by trained staff in an onsite testing facility (EMIT and TDx FPIA) are just as accurate as the immunoassay procedure performed by certified technicians in a commercial laboratory. 1 table, 2 figures, and 6 references