Analytical Performances of Human Immunodeficiency Virus Type 1 RNA-Based Amplix® Real-Time PCR Platform for HIV-1 RNA Quantification

Figure 3

Unweighted linear regression (a) and Passing-Bablok regression (b) tests between plasma HIV-1 RNA viral load measurements in 215 HIV-1-infected adults, expressed in log copies/mL obtained in parallel by the HIV-1 RNA-based Amplix real-time PCR assay (Biosynex) and the reference COBAS® AmpliPrep/COBAS TaqMan (CAP/CTM) HIV-1 test v2.0 (Roche Molecular Diagnostics). By unweighted linear regression, slope and Y-intercept values for the resultant trend line were 0.968 (95% CI, [0.933–1.002]) and 0.219 (95% CI, [0.080–0.357]), respectively. By Passing-Bablok regression, slope and -intercept values for the resultant trend line were 0.987 (95% CI, [0.968–1.009]) and 0.102 (95% CI, [0.009–0.186]), respectively. The diagonal dotted lines represent the ideal lines (no bias). The full lines represent the regression lines of the distribution.

(a) Unweighted linear regression

(b) Passing-Bablok regression