A test gives 90 true positives, 20 false positives, 10 false negatives and 80 true negatives. What is its positive predictive value?
Answer and explanation
Correct answer: D. 82%
- Step 1: PPV = TP / (TP + FP) = 90 / 110.
- Step 2: This equals 82%.
Answer
82%.
Why not the others: The other percentages are the other test characteristics (sensitivity, specificity, positive and negative predictive value), which use different denominators.
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