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NPV for Initial Negative Test Results by Assay or Specimen Type
| Comparison by | Group | Initial negative (n = 811) | True negative (n = 795) | False negative (n = 16) | NPV, % (95% CI) |
|---|---|---|---|---|---|
| Assay | CDC RT-PCR | 168 | 166 | 2 | 98.8 (95.7–99.7) |
| Simplexa Direct | 518 | 506 | 12 | 97.7 (96.2–98.6) | |
| TaqPath RT-PCR | 125 | 123 | 2 | 98.4 (94.6–99.5) | |
| Specimen type | Initial URT | 785 | 769 | 16 | 98.0 (96.9–98.7) |
| Initial LRT | 26 | 26 | 0 | 100 |
LRT, lower respiratory tract; NPV, negative predictive value; URT, upper respiratory tract.
