>Excuse the somewhat off-topic question. I need to do sample size
>calculations for a clinical trial with 4-5 arms. I've seen lots of
>calculations and examples for comparing two groups. Are there any
>special considerations that I should take into account when there are
>more than 2 groups? Adjusting p-values, etc.?
S+SeqTrial has support for multi-arm clinical trials
(though only for trials with a single analysis time;
for one- and two-arm trials it supports sequential designs).
For info see http://www.insightful.com/products/seqtrial
Tim Hesterberg
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| Tim Hesterberg Research Scientist |
| timh@insightful.com Insightful Corp. |
| (206)802-2319 1700 Westlake Ave. N, Suite 500 |
| (206)802-2500 (fax) Seattle, WA 98109-3044, U.S.A. |
| www.insightful.com/Hesterberg |
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Download the S+Resample library from www.insightful.com/downloads/libraries
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