Re: Re: Imaginary concentrations

> From: Nick Holford <[email protected]> > Subject: [NMusers] Re: Imaginary concentrations > To: [email protected] > Date: Monday, April 13, 2009, 11:55 PM > Hi, > > The OFV is computed using all observations. If you imagine > an > observation at time 0 then it will change the OFV. So my > advice is not > to imagine concentrations with MDV=0 but just use the > concentrations you > really measured. > > Nick > > ke fang wrote: > > Hi! > > Dear all! > > My samples were collected after a single intramuscular > injection. One individuals provies only one tissue samples > within the whole study. I found the MOFV were quite > different between the MDV was used or not. > > > > In my opinion, the concentration in tissue at T0 must > be 0 because of the intramuscular administration. So the > concentration at T0 was not a real observed 0 but a assumed > 0. The question was that if i treated the T0 concentration > as a MDV, the MOFV was quite different from treating it as a > real obesrved concentration. > > > > Whether the MDV should be used in my case? Can anyone > help me with this problem? > > > > Thanks in advance! > > > > > > Fang Ke > > > > > > > > > > -- > Nick Holford, Dept Pharmacology & Clinical > Pharmacology > University of Auckland, 85 Park Rd, Private Bag 92019, > Auckland, New Zealand > [email protected] > tel:+64(9)923-6730 fax:+64(9)373-7090 > mobile: +33 64 271-6369 (Apr 6-Jul 17 2009) > http://www.fmhs.auckland.ac.nz/sms/pharmacology/holford > > > Thanks to all! I've go thourgh the guide book of NONMEM and found the EVID term could seperate the dose from observation event. So i need not to use the MDV term.