Table 1.
Confusion Matrix Demonstrating the Real-World Assessment of SARS-CoV-2 Testing
| Test Result | Disease Present | Disease Absent | Total |
|---|---|---|---|
| First Test Positive | 693 (TP) | 0 (FP)a | 693 |
| First Test Negative | 16 (FN) | 1,262 (TN) | 1,278 |
| Total | 709 | 1,262 | 1,971 |
Note. TP, true positive; FN, false negative; TN, true negative; FP, false positive; NPV, negative predictive value. Observed false negative rate = 1 – sensitivity = FN/(TP + FN) = 16/709 = 2.3%.
a
All positive results were treated as true (resulting in quarantine). False-positive results were not assessed so full calculation of test performance, including specificity, is not possible.