A test gives 60 true positives, 30 false positives, 20 false negatives and 70 true negatives. What is its positive predictive value?
Answer and explanation
Correct answer: A. 67%
- Step 1: PPV = TP / (TP + FP) = 60 / 90.
- Step 2: This equals 67%.
Answer
67%.
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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