Performance characteristics of the COBAS AMPLICOR Hepatitis C Virus MONITOR Test, version 2.0

We evaluated the performance characteristics of the COBAS AMPLICOR Hepatiti s C Virus (HCV) MONITOR Test, version 2.0. Dilution studies using patient s pecimens demonstrated a lower limit of detection of 1,000 copies per millil iter: The assay was linear from 1,000 to 1 million HCV RNA copies per milli liter. Within-run precision and between-run precision were acceptable (appr oximately 0.100 and 0.14 SD for log(10)[copies per milliliter-]). A compari son of this version of the test (y), with the manual AMPLICOR HCV MONITOR T est, version 1.0 (x), yielded the following Deming regression equation: y = 1.004(+/- 0.04)x + 0.654(+/- 0.22); Sy/x\D = 0.336; n = 92; r2 = 0.846; r = 0.920. Further comparison of the COBAS version 2.0 assay (x) with the QUA NTIPLEX HCV bDNA Test (y) yielded the following Deming regression equation: y = 0.943 (+/- 0.130)x + 0.473 (+/- 0.717); S-y/x\D = 0.194; n = 26; r(2) = 0.600; r = 0.774. Version 2.0 detected the spectrum of HCV genotypes bett er than version 1.0.