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#1




c0uld s0me 0ne explain this biostastical qn...thnx
biostastics

#2




yuk.....this qn is making my head go in circles!
: 
#3




Cool question, where did you get if from?
So it sounds super difficult, with all the information given... but in fact I think it is super easy. The ask for the Number needed to treat which equals 1/absolute risk reduction The risk for both groups is given: 2,3% and 1,3% respectively so the NNT = 1 / (2,3%  1,3%) = 1/0,01 = 100 pretty straight forward if I got it correct Last edited by Curacao; 04182014 at 05:04 AM. 
#4




Quote:
ARR is absolute risk of placeboabsolute risk of rx.. . er... i think i just understood what u meant. just for clarity, could u put those values into the 2x2 table? (disease x risk), the plus n minus n all..? 
#5




this is an nbme 12 question so may spoil the assessment for someone the poster should have mentioned it and imo the answer is 2.3 since attributible risk reduction here is 2.3 minus 1.3 divided by 2.3 we get 1 divided by 2.3 as the attributable risk reduction if we inverse this we get 2.3 which is the number needed to treat correct me if i am wrong

The above post was thanked by:  
mihirkakara (12292014) 
#6




Thanks for the person posting the thread spoiling an NBME12 questions
My answer 100 is correct By the way, this question can be answered using google and has also been discussed in this forum before... nbme behav 
#7




Quote:
well there's no 2x2 table to set up, it is already in the question. It asks for the prevention of one congenital anomaly. The risk of all congenital anomalies in women taking Trace Elements is 2,3% Folic Adic is 1.3% ARR: 2.3%  1.3% = 1% NNT = 1/ARR = 1/1% = 1/0,01 = 100 
The above post was thanked by:  
dr rookie (04182014) 
#8




Quote:
awesome curacao, i got cold sweat when i saw this question in fact it IS EASY, "its always a TRAP" i have to keep myself repeating this for my exam hahaha, thanks for your explanation in fact it is 100.
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#9




s0rry guys !!
fr0m next time i will label it as an nbme qn anyways thanx f0r great ans wid explanati0n 
#10




Question lingers
Hi guys, I'm brand new. Sorry to dredge this up, but why, if the question asks for a congenital abnormality, do we not include neural tube defect and say NNT = 1/((2.3+.29)  1.3) = ~80?

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