Table 1.
Baseline demographics for participants, stratified by nasal swab RT-PCR result.
Fig 1.
SARS-CoV-2 Lineages of all RT-PCR or rapid antigen test (BinaxNOW) positive participants sequenced between January 1 and June 26, 2022.
Each vertical bar corresponds with one week. The height of each color segment within the bar corresponds with the percent of participants in that week whose sequences were identified as that color’s lineage. Abbreviations: Ct, cycle threshold; RT-PCR, reverse transcriptase polymerase chain reaction.
Fig 2.
SARS-CoV-2 RT-PCR Ct values and BinaxNOW rapid antigen test results of all RT-PCR positive participants tested between January 1 and June 26, 2022 (panel a) and stratified according to January or June test date (panels b and c). Average viral Ct values of all individuals with positive RT-PCR test results (N = 1321) are plotted in ascending order of Ct value. Each point represents one individual. Blue circles are individuals whose samples were positive on both rapid antigen test (BinaxNOW) and on RT-PCR test. Orange circles represent individuals who were RT-PCR positive but rapid antigen test negative. Abbreviations: Ct, cycle threshold; RT-PCR, reverse transcriptase polymerase chain reaction.
Fig 3.
SARS-CoV-2 RT-PCR Ct values and BinaxNOW rapid antigen test results of participants tested between January 1 and June 26, 2022, stratified by days since symptom onset for the January (a) and June (b) periods. Box plot shows first quartile, median, and third quartile in the shaded region; diamonds indicate outliers beyond 1.5 times the interquartile range. Blue circles overlaid are individuals whose samples were positive on both rapid antigen test (BinaxNOW) and on RT-PCR test. Orange circles represent individuals who were RT-PCR positive but rapid antigen test negative. Abbreviations: Ct, cycle threshold; RT-PCR, reverse transcriptase polymerase chain reaction.
Fig 4.
Results of Monte Carlo simulations to estimate the expected percent of participants that would be eligible for oral treatment evaluation based on results of SARS-CoV-2 RT-PCR or rapid antigen test (BinaxNOW) testing under different scenarios.
Each row corresponds to a different scenario; the top row uses conditions from January 2022 and the bottom row uses conditions from June 2022. The left column shows the distribution of SARS-CoV-2 RT-PCR Ct by days since symptom onset used as input into the simulations; orange dots correspond to participants who were RT-PCR positive but rapid antigen test negative and blue dots correspond to participants who were both RT-PCR and rapid antigen test positive. The right column show the resulting distributions of percent of participants who would be eligible for oral treatment evaluation based on RT-PCR (blue) versus rapid antigen test (orange) testing. These simulations assume 15% of participants with false negative rapid antigen tests will return and test positive three days after their initial test, and that RT-PCR test results will return after an average of 1 day. The mean difference, 95% confidence interval, and p-value are overlaid on the respective graphs, all calculated using the Monte Carlo simulations. Abbreviations: Ct, cycle threshold; RT-PCR, reverse transcriptase polymerase chain reaction.
Table 2.
Results of analysis comparing BinaxNOW to RT-PCR test under multiple assumptions.