Missing line of identity in predicted vs observed

[wilbertdew]

Hi All,

Sometimes, the line of identity does not show up in my predicted vs observed plot, anyone recognize this issue? When I add symbols to this line, I only see one upper right symbol. In the legend, I do see a dashed line for identity. Disabling side margins does not help.
Any help would be appreciated.

P.S. In this plot, Predicted is on the y-axis and observed on the x-axis, while I believe it should be the other way around. I could not find the option to change this, is this available? Could the default be changed or is there disagreement on which one should be on the y-axis?

[tobiasK2001]

Dear wilbertdew,

I never came across this. Which PK-sim version do you use? Is it possible to attach an example were ist shows up?

regarding Predicted vs Observed plot: as it is a y/x plot for me it would be OK for me to have the predicted on the y axis. I don't think there is a way to change it.

[wilbertdew]

Hi @tobiasK2001 ,

See for an example below. I have set the identity line to dash and symbols to diamond, but changing this doesn't help. Thanks for your help.

[wilbertdew]

Found the issue, there are a few BLQ data points coded as -1 in the observed data. This cannot be displayed on log scale of course and I should remove these before parameter identification. On linear scale I do see the line of identity.

[StephanSchaller]

Great find. Even then, the line of identity should not disappear. Can you report this within the PKSim Repository (PKSim-Forum) as a bug?

[Yuri05]

@wilbertdew Having negative valus in observed data will cause a lot of trouble anyway.
Please refer to the OSP documentation for:

• Import of <LLOQ values in observed data
• Handling of <LLOQ values in a Parameter Identification

[wilbertdew]

Thank you @Yuri05!
@StephanSchaller, I have just made an issue on the PKSim Repository.

[wilbertdew]

Problem solved by removing data points with negative values.
However, now my parameter identification throws an error, after which I cannot reopen the parameter identification. Everything runs as normal, I get results and diagnostics plot but at some point I get this error, which only happen with the dataset from which I removed some timepoints. Any ideas what is causing this? I already tried rebuilding the parameter identification from scratch.

[wilbertdew]

The last problem seems to be resolved by removing those individuals who had no data points left after removing the BLQ data points.

[msevestre]

This is a bug in the charting component