NONMEM Users Network Archive

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Re: FO vs FOCE

From: Nick Holford <n.holford>
Date: Wed, 10 Dec 2008 09:38:00 +1300


When the answers are known (i.e. the data is simulated) then FOCE is
always superior to FO. Whether the run converges or not make no
difference to the final model parameters.
I always use FOCE. I only use FO for teaching because of quicker run times.

If you want the wrong answer (quickly) then use FO and use the estimates
of OMEGA for future predictions :-)


Xiao, Alan wrote:
> Dear All,
> I know this is an old topic, too, but would like to see the statistics.
> When you have a dataset with about 10% of dense Phase II data (predose, 2, 4, 8, and 12 hrs post dose on day 1 and at steady state, twice-daily dose regimen) and about 90% of very sparse Phase III data (1-2 samples/patient), which method do you prefer: FO or FOCE? or FO for model development but FOCE for model refinement/finalization? If FOCE is not practical because of long run-time or numerical difficulties in converge, do you stop here or would you use FO?
> Thanks,
> Alan

Nick Holford, Dept Pharmacology & Clinical Pharmacology
University of Auckland, 85 Park Rd, Private Bag 92019, Auckland, New Zealand

Received on Tue Dec 09 2008 - 15:38:00 EST

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