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#1




Comparing two patient groups
I can't get my head around the following question. Could someone answer and explain plz. Here it goes....
Two drugs, X and Y are being evaluated for treatment of CHF. Pts receiving drug X have cardiac index of 2.5 L/m2 (square) with 95% CI 1.5 to 3.5. Pts on drug Y have cardiac index of 1.7 L/m2 with 95% 0.7 to 2.7. A test of the significance of difference shows a pvalue of 0.1. Which of the following is the likelihood that the difference in mean cardiac index of patients receiving drug X and drug Y is due to chance? A) 0% B) 2.5% C) 5% D) 7.5% E) 10% F) 66.7% G) 95% TBH, I don't even know WTH is it asking..... 
#3




Quote:
here the 2 drugs 95%CI are overlappingmeans there is no difference exist right? from kaplan videos....... correct me ,i always get confused with these thanks 
#4




Yes, if the 2 confidence intervals overlap that means the groups are not significantly different in their outcomes. And p value states the same thing p>0.05, which means there is no difference.

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venky2600 (10112012) 
#5




Quote:
i thought 0% as answer..as no difference exist... 
#6




In my opinion, you could choose A) 0% when p value is< 0.05.
p<0.05 means that there is a statistical significance between the 2 drugs, which means that there is almost 0% chances that the statistical difference between the 2 is by chance. 
The above post was thanked by:  
venky2600 (10112012) 
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BiostatisticsEpidemiology, Step1Questions 
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