Table. Results of Clinician-Collected Nasopharyngeal Swabs vs Home Self-collected Midnasal Swabs.
| Self-collected MNS swab result | Median (IQR or range) | Total | ||
|---|---|---|---|---|
| Clinician-collected NPS result | ||||
| Positive | Negative | Inconclusive | ||
| Positive, No. | 28 | 3 | 0 | 31 |
| NP swab viral load | 24.1 (18.7-26.0) | NA | NA | 24.1 (18.7-26.0) |
| Self-swab viral load | 22.6 (19.1-27.3) | 32.9 (32.7-33.2) | NA | 22.8 (19.3-28.4) |
| Days between symptom onset and NP swab | 3.0 (1.0-6.0) | 4.0 (2.5-8.5) | NA | 3.0 (1.0-6.0) |
| Days between MNS and NPS (range) | 1.0 (0.0-2.0) | 0.0 (0.0-0.0) | NA | 1.0 (0.0-2.0) |
| Negative, No. | 7 | 140 | 1 | 148 |
| NP swab viral load | 33.7 (33.5-35.1) | NA | 37.4 | 34.4 (33.5-36.8) |
| Self-swab viral load | NA | NA | NA | NA |
| Days between symptom onset and NP swab | 5.0 (2.5-13.0) | 2.0 (1.0-4.0) | 2.0 | 2.0 (1.0-4.0) |
| Days between MNS and NPS (range) | 1.0 (0.0-1.0) | 0.0 (−4.0 to 7.0) | 0.0 | 0.0 (−4.0 to 7.0) |
| Inconclusive, No.a | 3 | 3 | 0 | 6 |
| NP swab viral load | 32.9 (30.2-33.4) | NA | NA | 32.9 (30.2-33.4) |
| Self-swab viral load | 37.8 (37.3-37.9) | 37.0 (37.0-37.0) | NA | 37.4 (37.0-37.8) |
| Days between symptom onset and NP swab | 5.5 (5.3-5.8) | 1.5 (1.3-1.8) | NA | 3.5 (1.8-5.3) |
| Days between MNS and NPS (range) | 1.0 (1.0-1.0) | 0.0 (0.0-0.0) | NA | 0.5 (0.0-1.0) |
| Total, No. | 38 | 146 | 1 | 185 |
| NP swab viral load | 24.5 (21.9-30.1) | NA | 37.4 | 24.7 (22.3-31.8) |
| Self-swab viral load | 22.9 (19.4-28.8) | 33.4 (32.9-35.2) | NA | 24.9 (19.9-32.9) |
| Days between symptom onset and NP swab | 3.0 (2.0-6.0) | 2.0 (1.0-4.0) | 2.0 | 2.0 (1.0-5.0) |
| Days between MNS and NPS (range) | 1.0 (0.0-2.0) | 0.0 (−4.0 to 7.0) | 0.0 | 0.0 (−4.0 to 7.0) |
Abbreviations: IQR, interquartile range; MNS, midnasal swab; NA, not applicable; NPS, nasopharyngeal swab.
a
Positive result was defined as both of 2 primers positive, and inconclusive was defined as 1 of 2 probes for severe acute respiratory coronavirus 2 polymerase reaction positive and 1 negative.