VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 90% Sens / 94% Spec / 10% Prevalence

With 90% sensitivity, 94% specificity, and 10% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 62.5%.

Bayes Theorem: PPV = TP / (TP + FP) = (90% × 10%) / [(90% × 10%) + (6% × 90%)] = 62.5%.
FAQ: What is the PPV when sensitivity is 90%, specificity is 94%, and prevalence is 10%?

The Positive Predictive Value (PPV) is 62.5%, meaning 37.5% of positive results at 10% prevalence are false positives.