Hello, I would like to know if there is a way i can use this directly in Phoenix NLME without having to manipulate the dataset. A simple example would be if I have a parent metabolite dataset in NONMEM format. ID Time DV CMT 1 0 100 1 1 0 5 2 1 1 50 1 1 1 10 2 Is there a way to code this so i can have two different observe statements (for CObs, and C2Obs), but only having to map one column (DV) and specifying for example CMT == 1? CObs:C2Obs.
Hi Sagar, you can; but it’s really very easy with a pivot to turn it into the Phoenix default for this type of data; 
Which you can then easily build the model for with the graphical editor If that’s not suitable for you then I’ll have to have a poke around to remind myself how to code it this way. Simon 
Hi, How phoenix nlme is designed is to have a separate column for each kind of observation. This can be easily done using a simple data transformation the logic is below: if (CMT = 1 , PK= DV , BLANK) if (CMT =2, MET = DV, BLANK) so you create tow new columns for each type of DV now that does not really answer your question but that is what I recommend. In NLME you do not have to have two lines with the same time point you can have: ID Time PARENT MET 1 0 100 5 etc the caveat is that if you have mdv it will apply for both so keepign two separate lines gives you more flexibility ID Time PARENT MET MDV 1 0 100 1 1 0 5 0 To answer your question you can have conditional observe statement like this : observe(CObs = (C*(CMT==1) + C2*(CMT==2) ) + CEps * ( (CMT==1) + CMixRatio *(CMT==2)) ) CEps should appear once in each observe statement. [file name=cmtflag.phxproj size=662045]Certara | Drug Development Solutions (647 KB)