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#1




Biostatistics Q..
You are asked to evaluate the efficacy of new lipid lowering drug marked as "superstatin" results of randomized control trial at 5yrs are given at the table below
Treatment with Superstatin Treatment with Placebo M.Infarction 10 25 No M Infarction 990 975 what is the number needed to treat to prevent one myocardial infarction with superstatin. p:s i can't post the answer options because i wanna know how it's solved. Thanks!!!.... i'll post when it's done. 
#2




66.6
Attributable risk 25/100010/1000= 15/1000
No needed to treat= 1000/15=66.6
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#3




is that the correct asnwer?
isnt the forumla a/ a+b  c/c+d 
#4




Yea pathphisio thatz the correct answer..

#5




koolkiller,
In the 2x2 table, we're supposed to take 'a' as Diseased and Exposed right? So in this question, the 'a' cell is going to be patients with MI & who took placebo? Didn't understand how to arrive at that. Would appreciate your help, thanks! 
#6




NNT = 1/ARR= numbb. of people who were treated with the drug and had a MI subtracted by the number of ppl who had a MI taking placebo that = ARR and then do 1 /ARR

#7




Hope it help
Quote:
Attributable risk Incidence rate of exposed group minus incidence rate of non exposed group. So exposed group will be those who are on superstatin. In this question, if we make 2X2 table, then, Superstatin placebo MI 25 10 non MI 975 990
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#8




Quote:

#9




Ya true, Just took a proper look. Ok you can change it. I am never good at 2X2 tables.
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#10




Regardless, you taught me how to USE the formula. Thank you! Btw, when are you taking the Exam? I'm scheduled for October. Feel lousy!!

#11




I scheduled for Nov. YA "lousy feeling" is a common thing will all share.
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