Table 4.
Subanalysis Based on Duration of Illness
| Test Site(s) | Clinical Sensitivity, % (95% CI) | Clinical Specificity, % (95% CI) |
|---|---|---|
| Days of Illness | ||
| ≤7 d (n = 57) | ||
| Single sitea | ||
| Unilateral nasopharyngeal | 95.3 (83.0–99.1) | 100 (73.2–100) |
| Unilateral nasal midturbinate | 72.1 (56.1–84.2) | 100 (73.2–100) |
| Throat | 88.4 (74.1–95.6) | 100 (73.2–100) |
| Saliva (n = 57) | 44.2 (29.4–60.0) | 100 (73.2–100) |
| Saliva (N and ORF1ab assay; n = 53)5 | 56.4 (39.8–71.8) | 100 (73.2–100) |
| Combination of sitesc | ||
| Unilateral nasopharyngeal + Throat | 97.7 (86.2–99.9) | 100 (73.2–100) |
| Unilateral nasal midturbinate + Throat | 97.7 (86.2–99.9) | 100 (73.2–100) |
| Unilateral nasal midturbinate swab + salivaa | 79.1 (63.5–89.4) | 100 (73.2–100) |
| Throat swab + salivaa | 90.7 (76.9–97.0) | 100 (73.2–100) |
| >7 d (n = 48) | ||
| Single sitea | ||
| Unilateral nasopharyngeal | 70.0 (50.4–84.6) | 100 (78.1–100) |
| Unilateral nasal midturbinate | 46.7 (28.8–65.4) | 100 (78.1–100) |
| Throat | 66.7 (47.1–82.1) | 100 (78.1–100) |
| Saliva (n = 47) | 27.6 (13.4–47.5) | 100 (78.1–100) |
| Saliva (N and ORF1ab assay; n = 45)b | 44.4 (26.0–64.4) | 100 (78.1–100) |
| Combination of sitesc | ||
| Unilateral nasopharyngeal + throat | 83.3 (64.5–93.7) | 100 (78.1–100) |
| Unilateral nasal midturbinate + throat | 76.7 (57.3–89.4) | 100 (78.1–100) |
| Unilateral nasal midturbinate + saliva | 63.3 (43.9–79.5) | 100 (78.1–100) |
| Throat + saliva | 73.3 (53.8–87.0) | 100 (78.1–100) |
aAll samples (unless otherwise stated) were tested with the A*STAR Fortitude Kit (Accelerate Technologies, Singapore).
bA second polymerase chain reaction assay targeting the N and ORF1ab genes was used for saliva samples.
cFor data for sample site combinations, data from the A*STAR Fortitude Kit were used for saliva.