I have samples from individuals collected in plasma and then, 30 minutes later, in CSF.
The drug given has a well established one compartment model but nothing done for the CSF.
As I have samples from both, I am aiming to build a population model for both plasma and CSF.
1- Can phoenix model this in one model? That is, can I construct one model to characterize both at the same time or does this require separate modeling attempts?
2- If I can do this with one model, do I need to structure the data differently as there are multiple time points from different compartments with missing values? Can I use MDV for two separate observations?