Table 2 Calculating performance test-characteristics
Result/Signal | Gold standard (Listed events) | Total | Positive predictive value (PPV) = a / (a + b) | |
|---|---|---|---|---|
Labelled | Not labelled | Â | ||
Yes | a (true positive, TP) | b (false positive, FP) | a + b |  |
No | c (false negative, FN) | d (true negative, TN) | c + d | Negative predictive value (NPV) = d / (c + d) |
Total | a + c | b + d |  | |
Sensitivity = a/(a + c) | Specificity = d / (b + d) | |||