Re: variation of time values in output data

From: Leonid Gibiansky Date: April 20, 2015 technical Source: mail-archive.com
it could be rounding issue when the precision of the TIME in the data file exceeds the precision of the TIME in the output of the table. You could increase precision of the output using format statement (see manual). Other than that, NONMEM should not change TIME variable. Leonid -------------------------------------- Leonid Gibiansky, Ph.D. President, QuantPharm LLC web: www.quantpharm.com e-mail: LGibiansky at quantpharm.com tel: (301) 767 5566
Quoted reply history
On 4/20/2015 12:12 PM, Diane-Charlotte Imbs wrote: > Dear nonmem users, > > We used the option “-2 RATE” of NONMEM (actual rate of infusion is > unknown): within the control stream: > > D1=THETA(1) > > Moreover, since several infusions are given to the same patients, we > have added an inter-occasion variability on D1 (see code below)* > > We obtained nice fit BUT in the OUTPUT DATA: TIME values corresponding > to blood samples (and DV) are not identical to the actual TIME values of > the INPUT data !? > > It seems that NONMEM program adjusts rate values, their interoccasion > variability, and sampling times to have a good fit > > *How to fix TIME value corresponding to blood samples ? Indeed, we do > not know the actual infusion rate but we do know the sampling times.* > > ** > > Can anyone tell me if I chose the right model or help me resolving this? > > Thanks in advance, > > *$PK > > OCC1=0 > > OCC2=0 > > IF(DATE.EQ.1) OCC1=1 > > IF(DATE.EQ.2) OCC2=1 > > D1=THETA(1)*EXP(ETA(3)+ETA(4)*OCC1+ETA(5)*OCC2) > > $THETA (0,168,);D1 > > $OMEGA .1 ; iiv d1 > > $OMEGA BLOCK(1) .01 ; iov ETA4 OCC1 > > $OMEGA BLOCK(1) SAME ; iov ETA5 OCC2 > > *Loïc FIEVET* > > */Interne IPR en pharmacocinétique (1^er semestre)/* > > *Institut Universitaire du Cancer Toulouse - Oncopole* > > 1 avenue Irène Joliot-Curie > > 31059 TOULOUSE Cedex 9
Apr 20, 2015 Diane-Charlotte Imbs variation of time values in output data
Apr 20, 2015 Leonid Gibiansky Re: variation of time values in output data
Apr 21, 2015 Diane-Charlotte Imbs Re: variation of time values in output data
Apr 21, 2015 Mats Karlsson RE: variation of time values in output data
Apr 21, 2015 Klaas Prins RE: variation of time values in output data
Apr 21, 2015 Maria Kjellsson Re: variation of time values in output data