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RE: re st: sample size ?


From   amir gahremanpour <gamirali@hotmail.com>
To   statalist <statalist@hsphsun2.harvard.edu>
Subject   RE: re st: sample size ?
Date   Sun, 28 Aug 2011 14:20:38 -0500

thank you Ariel 

I did not know about "ralloc" at all but as far as I can tell it is a very useful program for just randomization. 
I need to calculate the sample size in a way that treatment/control ration is something like 2/1, or 3/1 and so on, rather than 1/1

Amir

----------------------------------------
> From: ariel.linden@gmail.com
> To: statalist@hsphsun2.harvard.edu
> Subject: re st: sample size ?
> Date: Sun, 28 Aug 2011 12:28:57 -0400
>
> Your subject title has nothing to do with your question. You are asking
> about treatment assignment, not calculating sample size or power (which
> these two programs you listed do).
>
> If you are interested in random allocation, I suggest you consider -ralloc-,
> a tremendously useful program written by Philip Ryan (findit -ralloc-). This
> program will allow you to allocate subjects in the ratio you desire. You can
> use this for the purpose of single treatment, cross-over or switchback
> designs.
>
> I hope this helps
>
> Ariel
>
> Date: Sun, 28 Aug 2011 00:11:08 -0500
> From: amir gahremanpour <gamirali@hotmail.com>
> Subject: st: sample size ?
>
> Dear statalisters
>
> How do I use stata to randomize the subjects to more than two groups for
> repeated measures but in a way that I assign two subjects to treatment group
> and one to control. For example treatment A 20 subjects, Treatment B 20 and
> control 10 subjects with 4 follow up time points. I am not sure if  sampsi
> or fpower can handle it.
>
> many thanks
>
>
>
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