Hello NONMEM Users,
Subjects received IV infusion (study 2), IV injection or SQ injection (study1).
In addition, I had to inject a dummy (amt=1) dose into the 3rd compartment,
which describes the target. 2 studies were integrated. The time-concentration
plots looked good for one study (IV injection or SC infusion) and
meaningless/really bad for the other one (IV infusion; population-predicted
values were a few-fold different from the observed ones). The data look
correct. The rate, dose, and times look fine (rate=amt/infusion_duration; the
first measure is taken after the end off infusion). When I set Rate=0 for the
second study, the outcome looks perfect for both studies; the objective
function decreased a lot. Because I do not feel comfortable using Rate=0, I
tried to change the order of the dummy and real doses, set time of the real
dose to 1 second, etc. Nothing works. It looks like a NONMEM bug.
Thank you,
Pavel
a potential bug
Pavel,
It is hard to tell what is going one without seeing the data file. The first idea is that RATE is incorrectly computed (e.g., incorrect time units). The controls stream and the data files with 1 dose and few observed data points would allow to check it.
Thanks
Leonid
--------------------------------------
Leonid Gibiansky, Ph.D.
President, QuantPharm LLC
web: www.quantpharm.com
e-mail: LGibiansky at quantpharm.com
tel: (301) 767 5566
[EMAIL PROTECTED] wrote:
> Hello NONMEM Users,
>
> Subjects received IV infusion (study 2), IV injection or SQ injection (study1). In addition, I had to inject a dummy (amt=1) dose into the 3^rd compartment, which describes the target. 2 studies were integrated. The time-concentration plots looked good for one study (IV injection or SC infusion) and meaningless/really bad for the other one (IV infusion; population-predicted values were a few-fold different from the observed ones). The data look correct. The rate, dose, and times look fine (rate=amt/infusion_duration; the first measure is taken after the end off infusion). When I set Rate=0 for the second study, the outcome looks perfect for both studies; the objective function decreased a lot. Because I do not feel comfortable using Rate=0, I tried to change the order of the dummy and real doses, set time of the real dose to 1 second, etc. Nothing works. It looks like a NONMEM bug.
>
> Thank you,
>
> Pavel
Hello Leonid,
I checked the data several times. The rates look fine. I'll send the modified
data to Tom.
Thanks,
Pavel
Quoted reply history
----- Original Message -----
From: Leonid Gibiansky
Date: Monday, September 29, 2008 6:31 pm
Subject: Re: [NMusers] a potential bug
To: [EMAIL PROTECTED]
Cc: nmusers
> Pavel,
> It is hard to tell what is going one without seeing the data
> file. The
> first idea is that RATE is incorrectly computed (e.g., incorrect
> time
> units).
> The controls stream and the data files with 1 dose and few
> observed data
> points would allow to check it.
> Thanks
> Leonid
>
> --------------------------------------
> Leonid Gibiansky, Ph.D.
> President, QuantPharm LLC
> web: www.quantpharm.com
> e-mail: LGibiansky at quantpharm.com
> tel: (301) 767 5566
>
>
>
>
> [EMAIL PROTECTED] wrote:
> > Hello NONMEM Users,
> >
> >
> >
> > Subjects received IV infusion (study 2), IV injection or SQ
> injection
> > (study1). In addition, I had to inject a dummy (amt=1) dose
> into the
> > 3^rd compartment, which describes the target. 2 studies were
> > integrated. The time-concentration plots looked good for one
> study (IV
> > injection or SC infusion) and meaningless/really bad for the
> other one
> > (IV infusion; population-predicted values were a few-fold
> different
> > from the observed ones). The data look correct. The rate,
> dose, and
> > times look fine (rate=amt/infusion_duration; the first measure
> is taken
> > after the end off infusion). When I set Rate=0 for the second
> study,
> > the outcome looks perfect for both studies; the objective
> function
> > decreased a lot. Because I do not feel comfortable using
> Rate=0, I
> > tried to change the order of the dummy and real doses, set
> time of the
> > real dose to 1 second, etc. Nothing works. It looks like a
> NONMEM bug.
> >
> >
> >
> > Thank you,
> >
> > Pavel
> >
> >
> >
>