USMLE Forum - Largest USMLE Community

Full Version: Stats help! - drpepper4u
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
I got this from the usmle.org sample questions and I can't figure out how to get that answer.

Several patients with hypertension whom you have treated for many years have recently had strokes. You are frustrated by this outcome and review the literature on the efficacy of anti hypertensive treatments in preventing stroke. A large, multicenter, randomized trials shows that a particular antihypertensive medication lowers the 5-Year risk for stroke from 8/1000 patients to 6/1000 patients, providing a relative risk reduction of 25%. Based on this study, the number of patients with hypertension who must be treated to prevent one stroke is which of the following?

(A) 4
(B) 75
© 250
(D) 500
(E) 2000
Sorry posted in wrong place
http://en.m.wikipedia.org/wiki/Number_needed_to_treat

Ready it and you will know the answer.