Comparison of NAT and PERT viral loads. A. Viral load measured by NAT and PERT at the time of diagnosis. PERT-derived viral loads were calculated based on the conversion shown in Figure 1. Samples below the limit of detection (LOD) were set to the LOD values as marked by the dotted lines. B. Ratio of PERT to NAT viral loads in the quantifiable range for PERT viral loads at the time of diagnosis and NAT viral loads measured at the time of diagnosis, during repeat testing and/or alternative (alt) testing with CTM2.0 or ARm2000. The area between dotted lines indicates changes in VL <3-fold. Symbols: ○ CTM1.0, ● CTM2.0, ♦ ARm2000, ■ CAM1.5, Δ PERT.