st: Converting standard error to standard deviation from meta-analysis

["Frank Peter" <frankpeter@Safe-mail.net>]

Dear Statalisters,

Please, I am trying to convert standard error to standard deviation from meta-analysis of proportion. Taking data from a recent post
http://www.stata.com/statalist/archive/2009-07/msg00097.html

input study cases total
1 20 1000
2 40 5000
3 30 1500
4 25 3300
end 


Is it valid if I get the SD like this?

r(seES)*sqrt(1000+5000+1500+3300)

OR

r(seES)*sqrt((1000+5000+1500+3300)/4)

I need the sd to calculate alpha and beta parameter for beta function - ibeta(a,b,x)

Thanks


Frank Peter
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