A new test for a condition was evaluated in 300 people. Of 100 who had the disease, 90 tested positive. Of 200 who did not, 30 tested positive. What is the sensitivity of the test?
Answer and explanation
Correct answer: D. 90 percent
- Step 1: Sensitivity is true positives divided by all people with the disease.
- Step 2: 90 of 100 diseased people tested positive, so 90 divided by 100 is 90 percent.
Answer
90 percent.
Why not the others: 94 percent: 94 percent is the negative predictive value (170 of 180 negatives). 85 percent: 85 percent is the specificity (170 of 200 healthy people). 75 percent: 75 percent is the positive predictive value (90 of 120 positives).
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