Evaluation of the accuracy of on-site multi-analyte drug testing devices in the determination of the prevalence of illicit drugs in drivers.

A principal goal of this research was to conduct a field evaluation of "on-site" multi-analyte drug testing devices to determine the most accurate, efficient, and cost-effective device available for the purpose of rapidly detecting drivers under the influence of drugs. Four on-site kits were selected and evaluated for accuracy and efficiency for the detection of tetrahydrocannabinol (THC), the cocaine metabolites (COC), and opiates (OPI). From 16 December 1995 to 17 March 1996, 303 voluntary urine specimens were collected by law enforcement officers from persons arrested for driving-under-the-influence (DUI). These specimens were tested using the four selected kits and aliquots of the specimens were sent to a DHHS certified lab for "gold standard" comparison testing by immunoassay and Gas Chromatography/Mass Spectrometry. On-site kit sensitivity ranged from 82.9% to 100% for THC, 82.5% to 100% for COC, and all were at 100% for OPI. Specificity, and positive and negative predictive values were also determined. Accuracy ranged from 94.0% to 98.3% for THC, 97.4% to 98.0% for COC, and 99.7% to 100% for OPI. All four kits were in very close agreement on prevalence: 15.5% to 15.8% for THC, all were at 13.2% for COC, and all were at 0.7% for OPI. For law enforcement purposes, sensitivity may be the most important indicator in these kits.