Antigen-detecting RDT results with a supervised self-collected anterior nasal (AN) swab and with a professional-collected nasopharyngeal (NP) swab in RT-PCR positive patients from combined oro-/nasopharyngeal swab
| No. | AN swab self-collected sd Q Ag-RDT | NP swab prof.-collected sd Q Ag-RDT | OP/NP swab RT-PCR | Symptom duration (days) | |
| CT value | Viral load+ | ||||
| 1 | pos (+++) | pos (+++) | 17.33# | 9.59 | 2 |
| 2 | pos (++) | pos (+++) | 17.86# | 9.43 | 1 |
| 3 | pos (+++) | pos (+++) | 18.01# | 9.38 | 1 |
| 4 | pos (++) | pos (+++) | 18.31# | 9.29 | 3 |
| 5 | pos (+++) | pos (+++) | 18.40# | 9.27 | 3 |
| 6 | pos (+++) | pos (+++) | 18.76# | 9.16 | 4 |
| 7 | pos (+++) | pos (+++) | 18.77# | 9.16 | 5 |
| 8 | pos (+++) | pos (+++) | 18.78# | 9.16 | 5 |
| 9 | pos (+++) | pos (+++) | 19.05# | 9.08 | 3 |
| 10 | pos. (+++) | pos. (+++) | 19.40# | 8.97 | 2 |
| 11 | neg. | pos (+++) | 19.66# | 8.90 | 1 |
| 12 | pos (+++) | pos (+++) | 20.32# | 8.70 | 3 |
| 13 | pos (+++) | pos (+++) | 17.81¶ | 8.68 | 4 |
| 14 | pos (++) | pos (+++) | 20.44# | 8.67 | 2 |
| 15 | pos (++) | pos (++) | 20.54# | 8.63 | 5 |
| 16 | pos (+++) | pos (+++) | 21.09# | 8.47 | 4 |
| 17 | pos (+++) | pos (+) | 18.62¶ | 8.44 | 4 |
| 18 | pos (+) | pos (++) | 21.87# | 8.24 | 7 |
| 19 | pos (++) | pos (+++) | 19.34¶ | 8.23 | 5 |
| 20 | pos (++) | pos (+++) | 22.05# | 8.19 | 2 |
| 21 | pos (+++) | pos (+++) | 19.47¶ | 8.19 | 6 |
| 22 | pos (+++) | pos (+++) | 22.60# | 8.03 | 6 |
| 23 | pos (+++) | pos (++) | 23.66# | 7.71 | 6 |
| 24 | pos (+) | pos (++) | 26.42# | 6.90 | 5 |
| 25 | pos (+++) | pos (+++) | 26.77# | 6.79 | 5 |
| 26 | neg. | neg. | 24.25¶ | 6.78 | 10 |
| 27 | pos (++) | pos (+++) | 24.77¶ | 6.62 | 4 |
| 28 | pos (+++) | pos (++) | 25.29¶ | 6.46 | 2 |
| 29 | pos (+) | pos (++) | 29.33# | 6.03 | 5 |
| 30 | neg. | neg. | 29.56# | 5.97 | 3 |
| 31 | neg. | neg. | 29.95# | 5.85 | 3 |
| 32 | pos (+) | pos (+) | 30.25# | 5.76 | 4 |
| 33 | neg. | neg. | 27.81¶ | 5.72 | 8 |
| 34 | pos (++) | pos (+) | 31.20# | 5.48 | 8 |
| 35 | neg. | pos (+) | 31.61# | 5.36 | 10 |
| 36 | neg. | neg. | 32.58# | 5.07 | 10 |
| 37 | neg. | neg. | 32.86# | 4.99 | 2 |
| 38 | neg. | neg. | 34.62# | 4.47 | 7 |
| 39 | neg. | neg. | 35.53# | 4.20 | 14 |
| Sensitivity 29/39 (74.4%) | Sensitivity 31/39 (79.5%) | ||||
| Positive percent agreement§ 90.6% (CI 75.8–96.8) | |||||
CT-values and viral load (in descending order) of the paired RT-PCR samples are shown, as well as the duration of symptoms per patient. The positive percent agreement between AN and NP samples on Ag-RDT, as well as the respective sensitivities compared to RT-PCR are shown.
Abbreviations: No.: patient number; sd Q: STANDARD Q COVID-19 Ag Test (sd Biosensor); Ag-RDT: antigen-detecting rapid diagnostic test; AN: anterior nasal; NP: nasopharyngeal; OP: oropharyngeal; CT: cycle threshold; RT-PCR: reverse transcription-polymerase chain reaction; neg.: negative; pos (+): weak positive; pos. (++): positive; pos. (+++): strong positive.
#Roche Cobas SARS-CoV-2 assay (E-gene, T2 target).
¶TibMolbiol assay, E-gene target.
+log10 RNA SARS-CoV2/swab.
§including 2 false positives on AN and 1 on NP.