VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 88% Sens / 84% Spec / 2% Prevalence

With 88% sensitivity, 84% specificity, and 2% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 10.1%.

Bayes Theorem: PPV = TP / (TP + FP) = (88% × 2%) / [(88% × 2%) + (16% × 98%)] = 10.1%.
FAQ: What is the PPV when sensitivity is 88%, specificity is 84%, and prevalence is 2%?

The Positive Predictive Value (PPV) is 10.1%, meaning 89.9% of positive results at 2% prevalence are false positives.