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Re: [NMusers] variation of time values in output data

From: Diane-Charlotte Imbs <diane.charlotte.imbs_at_gmail.com>
Date: Tue, 21 Apr 2015 11:46:31 +0200

Thank you, Leonid, for your answer but you can see (below) it’s not=
 a
rounding issue ; there are udge variations of time ?!!!


*INPUT FILE :*



ID DATE TIME DV AMT
RATE MDV EVID

3 1 0 0
2000 -2 1 1

3 1 2.6 1060
. . 0 0

3 1 170.1166667 331 .
. 0 0

3 2 170.1166667 . 2000
-2 1 1

3 2 172.1166667 1220 .
. 0 0

3 2 326.3333333 220 .
. 0 0

3 3 326.55 . 2000
-2 1 1

3 3 328.6166667 964 .
. 0 0

3 3 504.8333333 1260 .
. 0 0



*OUTPUT FILE :*



ID DATE TIME IPRED CL
D1 V1 IWRES

3 1 0 0
1.7711 113.17 35.217 0

3 1 2.6 1223 1.7711
113.17 35.217 -0.13328

3 1 170.12 567.29 1.7711
113.17 35.217 -0.41653

3 2 194.12 169.68 1.7711
112.49 35.217 -1

3 2 196.12 1114 1.7711
112.49 35.217 0.09514

3 2 350.33 1110 1.7711
112.49 35.217 -0.80181

3 3 374.55 328.36 1.7711
140.63 35.217 -1

3 3 376.62 1089.8 1.7711
140.63 35.217 -0.11542

3 3 552.83 1208.1 1.7711
140.63 35.217 0.04297





 Loïc FIEVET
Interne IPR en pharmacocinétique

Institut Universitaire du Cancer Toulouse - Oncopole
1 avenue Irène Joliot-Curie
31059 TOULOUSE Cedex 9








2015-04-20 19:21 GMT+02:00 Leonid Gibiansky <lgibiansky_at_quantpharm.com>:

> it could be rounding issue when the precision of the TIME in the data fil=
e
> exceeds the precision of the TIME in the output of the table. You could
> increase precision of the output using format statement (see manual). Oth=
er
> 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
>
>
>
> 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 i=
nfusion 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
>>
>>

Received on Tue Apr 21 2015 - 05:46:31 EDT

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