Performance characteristics of DRI, CEDIA, and REMEDi systems for preliminary tests of amphetamines and opiates in human urine.

Arrestee urine specimens (930) were tested with DRI, CEDIA, and REMEDi; those that tested positive for amphetamines and opiates (616 and 414, respectively) were then confirmed by gas chromatography-mass spectrometry. The performance characteristics of these three preliminary systems were evaluated using the following commonly used parameters: true positive, true negative, false positive, and false negative. The sensitivity, specificity, and efficiency of these methods were also calculated. Data derived from this study indicated DRI and CEDIA adapted by this study generated acceptable preliminary test results for amphetamine/methamphetamine and morphine/codeine, but not for MDA/MDMA and REMEDi has lower sensitivity than DRI and CEDIA, but with better specificity and efficiency, supporting its use under emergency room settings where drug concentrations in overdose cases are expectedly at high levels.