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estimating Ka from dataset combining rich sample study and sparse sampling study

From: Ethan Wu <ethan.wu75>
Date: Wed, 17 Jun 2009 08:20:41 -0700 (PDT)

Dear all,   I am working on this pop PK analysis. the objective is, t=
o explore some covariates on the exposure.   the dataset has rich=
 sampled study, with absorption phase well captured. and also sparse sampli=
ng study with only trough sample, and another sample around 1-2hr after dos=
ing  with rich sample study data, the ka and eta on Ka is well estimate=
d using FOCE INT method and 1ct 1st order model.  but when with pooled =
dataset, using the same model and method, eta on Ka is estimated to be =
almost 0, the fit to the data from rich sampled study became little worse o=
n the peak.   Is there way to keep a good estimation of Eta on Ka, wh=
ich is to make sure the good capture of Cmax, at least for rich sampled sub=
jects?  with my limited knowledge, I was thinking:  -- fixing Et=
a on ka with the estimate from rich sample study alone  -- hybrid estim=
ating methods  -- nonparametric method  Any comments will be hi=
ghly appreciated.
Received on Wed Jun 17 2009 - 11:20:41 EDT

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