Article Figures & Data
Figures
- FIG. 1.
Linear range of the viral load assays. (A) Bayer bDNA assay by laboratory; (B) Roche Monitor assay by laboratory (samples with a viral load greater than 5.0 log10 IU/ml were diluted 1:100 and retested); (C) Roche RT-PCR assay by laboratory; (D) Abbott RT-PCR by laboratory.
- FIG. 2.
Plot of the mean residual values for the viral load assays. Mean residual values are expressed as viral load minus the nominal concentration. Values are expressed as the means of all laboratories.
- FIG. 3.
Plot of the standard deviations (SD) for the viral load assays. The standard deviations have been calculated across all laboratories at tested log10 nominal HCV RNA values.
- FIG. 4.
Agreement plots between the Bayer bDNA and Abbott RT-PCR assays. The dotted line represents the mean difference for the samples.
- FIG. 5.
Agreement plots between the Bayer bDNA and Roche RT-PCR assays. The dotted line represents the mean difference for the samples.
Tables
- TABLE 1.
Sensitivity and specificity of the viral load assays
Assay No. positive/no. tested at the following sample concn (log10 IU/ml): 0 1.0 1.5 2.0 2.5 3.0 Bayer bDNA 2/28 0/28 3/28 13/28 Bayer TMA 1/7 7/7 7/7 7/7 7/7 7/7 Roche Monitor 0/28 13/28 22/28 27/28 Abbott RT-PCR 1/28 28/28 28/28 26/26a 27/27b 28/28 Roche RT-PCR 0/28 28/28 28/28 28/28 28/28 28/28 - TABLE 2.
Mean viral load values for the different assays (results are expressed as means for all laboratories)
Nominal concn (log10 IU/ml) Viral load (log10 IU/ml) by assay Roche Monitora Bayer bDNA Roche RT-PCR Abbott RT-PCR 1.0 1.17 0.99 1.5 1.96 1.59 2.0 2.51 2.17 2.5 2.87 2.59 3.0 2.86 3.32 3.16 4.0 4.17 3.95 4.19 4.25 4.5 4.61 5.0 5.03 5.5 5.58 5.39 5.65 5.63 6.0 6.14 5.87 6.19 6.17 6.5 6.59 6.32 6.69 6.68 7.0 7.06 —b 7.19 7.30 - TABLE 3.
Mean viral load values and standard deviations for the 89 clinical specimens
Assay Mean viral load (SD) (log10 IU/ml) and P by genotype Genotype 1 (n = 28) Genotype 2 (n = 25) Genotype 3 (n = 29) Genotype 4 (n = 7) Bayer bDNA 5.71 (0.86) 5.70 (0.96) 5.50 (0.77) 5.23 (0.41) Abbott RT-PCR 6.50 (1.09), P < 0.0001 6.31 (1.30), P < 0.0001 6.46 (0.72), P < 0.0001 5.31 (0.40), P = 0.42 Roche RT-PCR 6.53 (1.01), P < 0.0001 6.47 (1.14), P < 0.0001 5.78 (0.95), P < 0.004 5.08 (0.72), P = 0.36
