From: "Jiang, Xuemin" xjiang1@medicine.bsd.uchicago.edu
Subject: [NMusers] systematic difference 
Date: Wed, 4 Oct 2006 16:53:21 -0500 

Dear NMUSERS
 

I am using NONMEM to do population PK analysis. I am wondering how
to consider the systematic difference between two clinical sites.

Whether I can consider the systematic difference using the residual error model?
A combined error model is used. Whether I can code the systematic difference like this:

 
Y=F*EXP(EPS(1))+EPS(2)*SITE+EPS(3)*(1-SITE)

where site=1 or 0 which is stand for clinical site.

Thanks

Jim Jiang
University of Chicago
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