TABLE 4.
Diagnostic accuracy of an anti‐S1 ELISA (IgG) for the presence of previous COVID‐19 in various subgroups. Results of a diagnostic accuracy study are given (n = 3637)
| Subgroup | Numbers of patients | True positives | False negatives | False positives | True negatives | Sensitivity | Specificity |
|---|---|---|---|---|---|---|---|
| No. | No. | No. | No. | No. | Percent (95%CI) | Percent (95% CI) | |
| Patient population | |||||||
| Full study cohort | 3658 | 168 | 27 | 62 | 3401 | 86.2 (80.5, 90.7) | 98.2 (97.7, 98.6) |
| Inpatients | 1085 | 80 | 14 | 15 | 976 | 85.1 (76.3, 91.6) | 98.5 (97.5, 99.2) |
| Outpatients b | 2573 | 88 | 13 | 47 | 2438 | 87.1 (79.0, 93.0) | 98.1 (97.5, 98.6) |
| Gender | |||||||
| Male | 1147 | 81 | 6 | 18 | 1042 | 93.1 (85.6, 97.4) | 98.3 (97.3, 99.0) |
| Female | 2478 | 87 | 21 | 43 | 2348 | 80.6 (71.8, 87.5) | 98.2 (97.6, 98.7) |
| Age | |||||||
| <50 years | 2201 | 89 | 17 | 42 | 2070 | 84.0 (75.6, 90.4) | 98.0 (97.3, 98.6) |
| >50 years | 1457 | 79 | 10 | 20 | 1348 | 88.8 (80.3, 94.5) | 98.5 (97.8, 99.1) |
| Symptoms | |||||||
| Any symptom | 1985 | 143 | 25 | 39 | 1751 | 85.1 (78.8, 90.1) | 97.8 (97.0, 98.5) |
| No symptoms | 2473 | 88 | 13 | 47 | 2425 | 87.1 (79.0, 93.0) | 98.1 (97.5, 98.6) |
| Days since PCR | |||||||
| ≥28 | 3116 | 96 | 14 | 55 | 2951 | 87.3 (79.6, 92.9) | 98.2 (97.6, 98.6) |
| ≥21 | 3205 | 107 | 15 | 56 | 3027 | 87.7 (80.5, 93.0) | 98.2 (97.7, 98.6) |
| ≥14 | 3304 | 128 | 15 | 57 | 3104 | 89.5 (83.3, 94.0) | 98.2 (97.7, 98.6) |
a
Health‐care workers.