Fred Wolfe wrote
>  I am trying to compare the differences in means on a list of variables
>  between participant and comparison group. After obtaining the 
>  difference
>  for each variable, I want to run a t-test and test for significance.
You should look up the -foreach command
foreach var of varlist a b c d etc{
	ttest `var', by(group)
} 
and Si Li aked 
> Does this -foreach test need to assume independence between groups?
-foreach- is just a way of getting Stata to loop through  
the calculations. It is not statistical. 
For more information, please see the on-line help 
or the manual. 
Nick 
[email protected] 
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