VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 80% Sens / 88% Spec / 10% Prevalence

With 80% sensitivity, 88% specificity, and 10% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 42.6%.

Bayes Theorem: PPV = TP / (TP + FP) = (80% × 10%) / [(80% × 10%) + (12% × 90%)] = 42.6%.
FAQ: What is the PPV when sensitivity is 80%, specificity is 88%, and prevalence is 10%?

The Positive Predictive Value (PPV) is 42.6%, meaning 57.4% of positive results at 10% prevalence are false positives.