E***a 发帖数: 60 | 1 a study is done to determine if raloxifene will decrease the incidence of
vertebral fractures in postmenopausal women. The results are shown:
number of women in study group Raloxifene 2557 , Placebo 2576
number of verterbal fractures 138 260
(5.4%) (10.1%)
How many women need to be treated to prevent 1 vertebral fracture?
A. 100/5.4=18.5
B. 100/10.1=10
C. 100/(10.1+5.4)=6.5
D. 100/(10.1-5.4)=21
E. 100/(10.1 x 5.4)=2
why not D, the answer is E from feedback,although cannot understand why?????
? | g*******g 发帖数: 196 | | w***e 发帖数: 269 | | E***a 发帖数: 60 | 4 有人说form7也出现过这道题,官网给的答案依然是E,虽然也不理解为什麽.NNT=1/ARR
D 应该是答案啊. |
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