VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 82% Sens / 92% Spec / 2% Prevalence

With 82% sensitivity, 92% specificity, and 2% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 17.3%.

Bayes Theorem: PPV = TP / (TP + FP) = (82% × 2%) / [(82% × 2%) + (8% × 98%)] = 17.3%.
FAQ: What is the PPV when sensitivity is 82%, specificity is 92%, and prevalence is 2%?

The Positive Predictive Value (PPV) is 17.3%, meaning 82.7% of positive results at 2% prevalence are false positives.