VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 94% Sens / 88% Spec / 2% Prevalence

With 94% sensitivity, 88% specificity, and 2% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 13.8%.

Bayes Theorem: PPV = TP / (TP + FP) = (94% × 2%) / [(94% × 2%) + (12% × 98%)] = 13.8%.
FAQ: What is the PPV when sensitivity is 94%, specificity is 88%, and prevalence is 2%?

The Positive Predictive Value (PPV) is 13.8%, meaning 86.2% of positive results at 2% prevalence are false positives.