I work in a research group that is about to build a multiyear data 
structure to support research.  Historically, data management strategies 
have resulted in multiple derivative versions of key variables and 
concepts  - for example, imagine a continuous variable that is then 
variously categorized, variously trimmed, etc..  A whole cluster of 
derived variables results, but the underlying do files are not uniformly 
preserved.  This undermines the integrity of the resulting derivative 
datasets.  I think this is a pretty typical story. 
Clearly we are not alone in this challenge. In SAS I might generate a 
root set of variables, and then do my trims and recoding through a 
variety of format statements which I could electively  attach to the 
core variables. However, that concept doesn't quite fit STATA.  
Therefore, I'd invite suggestions on how you are managing this sort of 
data integrity/documentation problem within STATA environments.
Thanks,
Rob
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