VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING
Bayesian Positive Predictive Value: 94% Sens / 92% Spec / 2% Prevalence
With 94% sensitivity, 92% specificity, and 2% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 19.3%.
Bayes Theorem: PPV = TP / (TP + FP) = (94% × 2%) / [(94% × 2%) + (8% × 98%)] = 19.3%.
FAQ: What is the PPV when sensitivity is 94%, specificity is 92%, and prevalence is 2%?
The Positive Predictive Value (PPV) is 19.3%, meaning 80.7% of positive results at 2% prevalence are false positives.