Evaluation of the ETS and ADx urine drug screening immunoassay analyzers

The Syva ETS and Abbott ADx urine drug testing immunoassay systems were evaluated for analytical performance, ease of operation, data processing, and time of analysis. Urine specimens were analyzed by each system for six drugs of abuse. Discrepancies in drug detection were due to variations in the cut-off concentrations between ADx and EMIT d.a.u. (ETS) reagents. The ETS was found to have several major advantages over the ADx: greater sample load, more convenient "random access," and real time data processing. When analyzing multiple specimens, the turnaround time for the ETS as compared to the ADx was twice as fast for the six-analyte assay. The ADx assay calibrations were stable for two weeks, while the ETS required daily calibration with verification by cut-off calibrators every eight hours. The ETS was found superior to the ADx for multianalyte urine drug screening.