How to best utilize the Partial Derivatives Plots in WNL model

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1

Hi

I have been struggling to make head or tales of the partial derivative plot provided in the WNL output after fitting. How would I interpret or used the information on these graphs. I know how to interpret most of the other out put but this one is a head scratcher.

Thanks in advance.

2

Hello mjPK,

The partial derivative plot is not helpful in determining if a model is a good fit to the data. However, in some cases, it could be helpful to plan future studies with that drug (assuming your model is correct). Partial derivative is the predicted function with respect ot each of the parameters in the model and it gives the times of maximal sensitivity of the model with respect to changes in the parameters. Ideally, one would sample (next time around) where the partial derivatives exhibit an extreme value.

Note that these plots are not useful for a multiplicative error model.

Hope this helps,

Ana Henry

Certara Customer Education