VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 88% Sens / 96% Spec / 2% Prevalence

With 88% sensitivity, 96% specificity, and 2% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 31.0%.

Bayes Theorem: PPV = TP / (TP + FP) = (88% × 2%) / [(88% × 2%) + (4% × 98%)] = 31.0%.
FAQ: What is the PPV when sensitivity is 88%, specificity is 96%, and prevalence is 2%?

The Positive Predictive Value (PPV) is 31.0%, meaning 69.0% of positive results at 2% prevalence are false positives.