VITAL DX v4.0 • VERIFIED QUANTITATIVE BRIEFING

Bayesian Positive Predictive Value: 98% Sens / 90% Spec / 10% Prevalence

With 98% sensitivity, 90% specificity, and 10% disease prevalence, the Positive Predictive Value (PPV) of a positive test is 52.1%.

Bayes Theorem: PPV = TP / (TP + FP) = (98% × 10%) / [(98% × 10%) + (10% × 90%)] = 52.1%.
FAQ: What is the PPV when sensitivity is 98%, specificity is 90%, and prevalence is 10%?

The Positive Predictive Value (PPV) is 52.1%, meaning 47.9% of positive results at 10% prevalence are false positives.