VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 92% Sens / 96% Spec / 2% Prevalence

With 92% sensitivity, 96% specificity, and 2% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 31.9%.

Bayes Theorem: PPV = TP / (TP + FP) = (92% × 2%) / [(92% × 2%) + (4% × 98%)] = 31.9%.
FAQ: What is the PPV when sensitivity is 92%, specificity is 96%, and prevalence is 2%?

The Positive Predictive Value (PPV) is 31.9%, meaning 68.1% of positive results at 2% prevalence are false positives.