Test measures
Reference standard | Outcome | Test measures | ||
Positive | Negative | |||
Diagnostic algorithm | ||||
Positive | True positives correctly identified (A) | False positives (B) | Total identified as positive | PPV=A/(A+B) |
Negative | False negatives (C) | True negatives correctly identified (D) | Total identified as negative | NPV=D/(C+D) |
Outcome | True positives | True negatives | ||
Test measures | Sensitivity=A/(A+C) | Specificity=D/(B+D) |