VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING
Bayesian Positive Predictive Value: 80% Sens / 86% Spec / 10% Prevalence
With 80% sensitivity, 86% specificity, and 10% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 38.8%.
Bayes Theorem: PPV = TP / (TP + FP) = (80% × 10%) / [(80% × 10%) + (14% × 90%)] = 38.8%.
FAQ: What is the PPV when sensitivity is 80%, specificity is 86%, and prevalence is 10%?
The Positive Predictive Value (PPV) is 38.8%, meaning 61.2% of positive results at 10% prevalence are false positives.