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  #1  
Old 08-18-2011
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Default compare the efficacacy

In a clinical trial of Xtrmnate, a new antibiotic, 300 hypotensive patients requiring vasopressor therapy were randomly assigned to 3 trial arms. One arm received penicillin G. A second arm received vancomycin (the current gold standard). The third arm received Xtrmnate. The primary end point to be evaluated was the mean duration of treatment with vasopressors.
Which of the following can be used to compare the efficacy of Xtrmnate with regards to the primary endpoint?
A. Studentís t-test
B. Analysis of variance
C. Correlation coefficient
D. Chi-square testing
E. Standard error of the mean
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Old 08-18-2011
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Default Anova

i think anova: used to compare means between 3 or groups

students t test to compare means of 2 groups

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Originally Posted by ricko335 View Post
In a clinical trial of Xtrmnate, a new antibiotic, 300 hypotensive patients requiring vasopressor therapy were randomly assigned to 3 trial arms. One arm received penicillin G. A second arm received vancomycin (the current gold standard). The third arm received Xtrmnate. The primary end point to be evaluated was the mean duration of treatment with vasopressors.
Which of the following can be used to compare the efficacy of Xtrmnate with regards to the primary endpoint?
A. Studentís t-test
B. Analysis of variance
C. Correlation coefficient
D. Chi-square testing
E. Standard error of the mean
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  #3  
Old 08-18-2011
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Default

it is B) ANOVA, as endpoint is duration of treatment (numerical)if endpoint would be something like number of good or bad outcome, might be Chi-square (categorical)
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Old 08-19-2011
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Correct Answer

The correct answer is B.
The question asks how the mean of a continuous measure (the duration of vasopressor treatment) can be compared between 3 groups. A standard statistical approach to use is ANOVA.
If two groups were being compared, t-test would be adequate. Chi-square testing is used for comparing categorical measures. SEM and correlation coefficient cannot be used to evaluate the mean of a distribution.
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