[no subject]

I'd start with the most problematic file 
and check for missing values. 

You can also loop over your suspect files, say 

clear 

foreach subj of numlist 50910 119669 /*
*/ 209171 ... {
	use ...`subj', clear 
	di "`subj'" 
	count 
	count if missing(subjid) 
	di 
} 

Nick 
n.j.cox@durham.ac.uk 
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