TABLE 1.

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

Time pointHCV RNA levelSensitivity (%)aSpecificity (%)bPPV (%)cNPV (%)d
Baseline<400,000 IU/ml3210010051
Day 21<10,000 IU/ml7110010070
Day 21<100,000 IU/ml87768480
Wk 4<1,000 IU/ml68959568
Wk 4<15 IU/ml (negative)4810010058
Wk 4<450,000 IU/ml97366889
Wk 12<50 IU/ml (negative)93959791
Wk 12<15 IU/ml (negative)90959788
Second slopee>0.70 log IU/wk74919271
Second slopee>0.35 log IU/wk97738394
Second slopef>0.70 log IU/wk71959670
Second slopef>0.35 log IU/wk1007384100
Decrease, day 4>1.5 log IU4510010053
Decrease, wk 12>2 log IU1005074100
  • a Sensitivity, proportion of patients with SVR who had HCV RNA levels below, a slope value above, or HCV RNA reduction above the given limit.

  • b Specificity, 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.

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

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

  • e Based on HCV RNA levels at days 7, 14, and 21.

  • f Based on all HCV RNA values.