Table 1.
Overview of the results for each saliva method compared to the nasopharyngeal swab.
| ORAcollectTM (RT-PCR) |
V-ChekTM (AgRDT) |
Whistling TestTM (AgRDT) |
|
|---|---|---|---|
| True positives | 100 (28.8%) | 1 (1.9%) | 5 (4.1%) |
| True negatives | 218 (62.8%) | 37 (68.5%) | 47 (38.2%) |
| False positives | 8 (2.3%) | 0 (0.0%) | 0 (0.0%) |
| False negatives | 21 (6.1%) | 12 (22.2%) | 50 (40.7%) |
| Invalid results | 0 (0.0%) | 4 (7.4%) | 21 (17.1%) |
| Total number of samples | 347 | 54 | 123 |
| Sensitivity | 82.6% | 7.7% | 9.1% |
| Specificity b | 96.5%/99.1% b | 100% | 100% |
| NPV a | 91.3% | 66.9% | 67.3% |
| PPV a,b | 92.6%/98.0% b | 100% | 100% |
a NPV and PPV were calculated based on a disease prevalence of 34.8%; b the recalculated values for specificity and positive predictive value (PPV) after correction of the data for the 6 false positive cases who retested positive for SARS-COV-2 by nasopharyngeal sampling within 2–9 days.