TABLE 1.

Predictive values of HCV RNA levels and changes at different time points

Time point	HCV RNA level	Sensitivity (%)a	Specificity (%)b	PPV (%)c	NPV (%)d
Baseline	<400,000 IU/ml	32	100	100	51
Day 21	<10,000 IU/ml	71	100	100	70
Day 21	<100,000 IU/ml	87	76	84	80
Wk 4	<1,000 IU/ml	68	95	95	68
Wk 4	<15 IU/ml (negative)	48	100	100	58
Wk 4	<450,000 IU/ml	97	36	68	89
Wk 12	<50 IU/ml (negative)	93	95	97	91
Wk 12	<15 IU/ml (negative)	90	95	97	88
Second slopee	>0.70 log IU/wk	74	91	92	71
Second slopee	>0.35 log IU/wk	97	73	83	94
Second slopef	>0.70 log IU/wk	71	95	96	70
Second slopef	>0.35 log IU/wk	100	73	84	100
Decrease, day 4	>1.5 log IU	45	100	100	53
Decrease, wk 12	>2 log IU	100	50	74	100

^aSensitivity, proportion of patients with SVR who had HCV RNA levels below, a slope value above, or HCV RNA reduction above the given limit.

^bSpecificity, proportion of patients with non-SVR who did not have HCV RNA below, a slope value above, or HCV RNA reduction above the given limit.

^cPPV, proportion of patients with HCV RNA below, a slope value above, or HCV RNA reduction above the given limit who achieved SVR.

^dNPV, proportion of patients without HCV RNA below, a slope value above, or HCV RNA reduction above the given limit who did not achieve SVR.

^eBased on HCV RNA levels at days 7, 14, and 21.

^fBased on all HCV RNA values.