VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 82% Sens / 96% Spec / 2% Prevalence

With 82% sensitivity, 96% specificity, and 2% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 29.5%.

Bayes Theorem: PPV = TP / (TP + FP) = (82% × 2%) / [(82% × 2%) + (4% × 98%)] = 29.5%.
FAQ: What is the PPV when sensitivity is 82%, specificity is 96%, and prevalence is 2%?

The Positive Predictive Value (PPV) is 29.5%, meaning 70.5% of positive results at 2% prevalence are false positives.