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Re: [NMusers] DEFDOSE/DEFOBS Required for Many Compartments?

From: Sven Mensing <>
Date: Mon, 01 May 2017 18:14:01 +0000

Hi Bill,

I recall some indexing issue in NONMEM with above 40 compartments. Please
try something like NCOMP=43 or greater.

Kind regards


Bill Denney <> schrieb am Mo. 1. Mai 2017 um

> Hi,
> I have a model with many compartments (42 different compartments are
> defined). It is currently setup this way to future-proof the dataset in
> case we want to combine analyses of many drugs (about 20 different drugs
> with central/peripheral compartments) and several endpoints.
> In the current model, I'm only fitting the PK of one drug, so only two of
> the compartments are enabled: compartments 39 and 42. After the IGNORE
> statement, the data is relatively small with 400 records between 16
> subjects, and all the data are in compartment 39 (the central compartment
> for the current drug).
> CMT, EVID, and MDV (along with everything else) is correctly specified.
> When I run the model with CMT 39 defined by:
> COMP=(PKCENT) ; 39 central PK compartment (ug/mL)
> the model fails with the error "COMPARTMENT ASSOCIATED WITH THE PREDICTION
> IS OFF" noted for all the dosing rows, but when I specify that compartment
> 39 is the default observation and dose compartment (due to IV dosing), the
> model works.
> COMP=(PKCENT,DEFOBS,DEFDOSE) ; 39 central PK compartment (ug/mL)
> I thought that when CMT and EVID are specified, DEFOBS and DEFDOSE are not
> important.
> Does anyone know why adding DEFOBS and DEFDOSE fixed my model?
> Thanks,
> Bill
> ------------------------------
> [image: Human Predictions Logo] <>*William
> S. Denney, PhD*
> Chief Scientist, Human Predictions LLC
> +1-617-899-8123
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Received on Mon May 01 2017 - 14:14:01 EDT

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