Re: analysis of non-positive DV

Have a look at those two references: J Pharmacokinet Pharmacodyn. 2009 Oct;36(5):381-405. Epub 2009 Aug 21. Methods of utilizing baseline values for indirect response models. Woo S, Pawaskar D, Jusko WJ. J Pharmacokinet Pharmacodyn. 2008 Jun;35(3):269-83. Epub 2008 Apr 30. Approaches to handling pharmacodynamic baseline responses. Dansirikul C, Silber HE, Karlsson MO. Vinogradova Svetlana wrote: > Dear NONMEM users, > > I'm analyzing a dataset of 4 patients, there are 2 types of observations for each patient > - vehicle (say baseline) and dose (treatment). We want to analyze our dataset in terms of > (treatment-baseline). So I've modified my dataset, and now I have only one > "column" of observations for each patient: DV= (treatment-baseline). But now I > have some problems because I have some negitive values in DV column. In case of some > models it results in problems, for example: > > TEFF = TBAS + (TSLP*CP)**TALP > > so TSLP should be positive but it's not that right... > > Maybe there are some common methods to deal with this case? > > Thanks a lot, > Svetlana