In a trial the event rate was 25 percent in the control group and 15 percent in the treatment group. What is the relative risk reduction?
Answer and explanation
Correct answer: D. 40 percent
- Step 1: RRR is the absolute risk reduction divided by the control event rate.
- Step 2: ARR = 25 percent minus 15 percent = 10 percent. RRR = 10 divided by 25 = 40 percent.
Answer
40 percent.
Why not the others: 60 percent: 60 percent is the relative risk (15 divided by 25). 10 percent: 10 percent is the absolute risk reduction. 67 percent: 67 percent is the control rate divided by the treated rate minus one.
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