Figure 2.

Comparison of Binax-CoV2 test with quantitative reverse-transcription polymerase chain reaction (RT-PCR) test. A, Average viral cycle threshold (Ct) values from all 26 RT-PCR–positive individuals from the community study, plotted in ascending order. Blue circles indicate Binax-CoV2–positive samples; yellow squares, Binax-CoV2–negative samples. Open symbols represent individuals who were asymptomatic on the day of the test and filled symbols, those who reported symptoms on that day. B, Normalized sample band signal from retrospective image analysis of Binax-CoV2 cards was plotted as a function of Ct value for all available scanner images (19 of 26 RT-PCR–positive samples and a random subset of RT-PCR–negative samples). Binax-CoV2 true-positives are shown in blue and labeled TP; false-negatives, shown in yellow and labeled FN; and true-negatives, shown in red and labeled TN. C, Corresponding Binax-CoV2 card images from the data in B.