Table 3. Sensitivity, specificity, PPV, and NPV of proxy calculations by lineage.
| Presumed Alpha | ||||
| Alpha (Samples Collected: 1/1/2021-12/03/2021; n = 273,318) | Sensitivity | Specificity | PPV | NPV |
| SGTF | 79.3% | 99.6% | 96.5% | 97.4% |
| rSGTP + SGTF | 96.4% | 99.5% | 96.4% | 99.5% |
| Presumed Omicron B.1.1.529/BA.1/BA.1.1 | ||||
| Omicron - B.1.1.529/BA.1/BA.1.1 (Samples Collected: 11/24/2021-3/23/2022; n = 105,646) | Sensitivity | Specificity | PPV | NPV |
| SGTF | 92.2% | 97.8% | 99.2% | 80.2% |
| rSGTP + SGTF | 99.6% | 97.6% | 99.2% | 98.9% |
| Presumed Omicron BA.2 | ||||
| Omicron—BA.2 (Samples Collected: 1/3/2022-3/23/2022; n =: 59,920) | Sensitivity | Specificity | PPV | NPV |
| Inverse SGTF | 99.7% | 94.1% | 53.1% | 100.0% |
| Inverse rSGTP + SGTF | 99.7% | 99.1% | 88.0% | 100.0% |