VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING
Bayesian Positive Predictive Value: 92% Sens / 90% Spec / 2% Prevalence
With 92% sensitivity, 90% specificity, and 2% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 15.8%.
Bayes Theorem: PPV = TP / (TP + FP) = (92% × 2%) / [(92% × 2%) + (10% × 98%)] = 15.8%.
FAQ: What is the PPV when sensitivity is 92%, specificity is 90%, and prevalence is 2%?
The Positive Predictive Value (PPV) is 15.8%, meaning 84.2% of positive results at 2% prevalence are false positives.