VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 84% Sens / 98% Spec / 10% Prevalence

With 84% sensitivity, 98% specificity, and 10% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 82.4%.

Bayes Theorem: PPV = TP / (TP + FP) = (84% × 10%) / [(84% × 10%) + (2% × 90%)] = 82.4%.
FAQ: What is the PPV when sensitivity is 84%, specificity is 98%, and prevalence is 10%?

The Positive Predictive Value (PPV) is 82.4%, meaning 17.6% of positive results at 10% prevalence are false positives.