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[NMusers] covariate on transit compartment model parameters

From: Jing Niu <>
Date: Sun, 25 Sep 2016 08:40:37 -0400

Dear NMusers,
I am modeling long-acting injectable formulation using transit compartment
model parameterized with mtt (mean transit time) and ntr (number of transit
compartment). As I would like to model multiple formulations using the same
structure model, adding formulation as a categorical covariate on mtt or
ntr separately decreased the OFV significantly (by ~100 units). Considering
mtt and ntr are correlated parameters, should I add formulation on both
mtt and ntr, or adding to either one is sufficient?
Any input is greatly appreciated,

PS: I am considering the latter one, due to that the simulations with
changing Ktr or ntr generated similar profiles (Fig1 c and d,

Received on Sun Sep 25 2016 - 08:40:37 EDT

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