TABLE 4.

Genotype reactivity of the COBAS AMPLICOR and AMPLICOR HCV MONITOR tests

Format	Genotype	Log10 measured concentration − log10 expected concentrationa (IU/ml)
		3.5 log10	4.5 log10	5.5 log10b
COBAS AMPLICOR	1a	0.2	0.1	−0.1
	1b	0.3	0.2	0.1
	2a	0.4	0.4	0.1
	2b	0.2	0.1	−0.1
	3a	0.0	0.0	−0.2
AMPLICOR	1a	0.2	0.0	−0.2
	1b	0.3	0.2	0.1
	2a	0.4	0.3	0.0
	2b	0.4	0.2	−0.1
	3a	−0.1	−0.2	−0.3

^aHigh-concentration clinical specimens were diluted to the indicated log₁₀ concentration (international units per milliliter). For each sample, results for six replicates were averaged and log₁₀-transformed prior to calculating the difference between the measured and expected log₁₀ titers. The expected concentration was originally measured by performing both the COBAS AMPLICOR and AMPLICOR HCV MONITOR v2.0 tests on a sample of the original specimen that was diluted to achieve a concentration near the middle of the linear range. 

^bFor genotype 1b only, the input concentration was 5.2 log₁₀ IU/ml.