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AW: Time 'T' in $Error

From: Katrin Volz <ankekatrin.volz>
Date: Tue, 28 Jul 2015 08:07:56 +0200

Dear Bill, dear all

Thanks so much for your answer.

 

More concrete I would like to model blood pressure including a circadian
rhythm. Therefore I would like to use a sine or cosine function with =
‘T’
instead of ‘Time’.

SinfS = ( 1 + Amplitude * sin ( (2*PI/Period) * (T-Phase) ) ) ; sine =
or
cosine function

SBP = (SBas + SinfS) * (1-EffS)
; SBP = systolic blood pressure, SBas = Baseline systolic blood =
pressure,
(1-EffS = effect)

I could also model this effect using a turnover model and avoid this
problem, but I would like to evaluate this kind of PD model (if there is =
any
meaningful way to code).

I also had the idea to code this sine function as a function of time in =
a
compartment and rename this compartment in $Error, but I am not sure if
there is any way to do this.

 

Thanks again and best regards.

Katrin

 

Von: Denney, William S. [mailto:William.S.Denney
Gesendet: 27 July 2015 17:34
An: Katrin Volz <ankekatrin.volz
nmusers
Betreff: RE: [NMusers] Time 'T' in $Error

 

Hi Katrin,

 

$ERROR is executed once per data row. The time when $ERROR is run is =
the
TIME value (the discrete times of the measurement). For this specific
example, you can just use TIME. You will need to code your $DES block =
so
that what you’re wanting to integrate as a function of time is in a
compartment amount (e.g. A(1)). With your example, it’s hard to see =
how T
is used in the $DES, but perhaps you could share the real example to =
give a
bit more concrete advice on how to integrate the answer into your code.

 

Thanks,

 

Bill

 

From: owner-nmusers
[mailto:owner-nmusers
Sent: Monday, July 27, 2015 10:46 AM
To: nmusers
Subject: [NMusers] Time 'T' in $Error

 

Dear NMuser,

 

I would like to model a PD effect using a function which includes =
continuous
time ‘ T ’.

 

The PD Effect is coded in $Error.

In general like this:

$ERROR

MyFunction = xxx + T

PDEffect = Basline * MyFunction

 

But ‘T’ cannot be used in $Error.

 

I tried to code the function with ‘T’ in $DES and rename it to use =
it in
$ERROR:

 

$DES

MyFunction = xxx + T

$ERROR

MyNewFunction = MyFunction

PDEffect = Baseline * MyNewFunction

 

but it didn’t worked (to rename was not permitted by NONMEM).

 

Does anyone of you has an idea how to solve this problem?

 

Thanks and best regards.

Katrin

 

 

 

Anke-Katrin Volz

PhD Student

Saarland University

Clinical Pharmacy

Campus C2 2 | Room 0.31

D- 66123 Saarbrücken

 

mail ankekatrin.volz
<mailto:ankekatrin.volz

fon +49 [0]681 302 22 84

fax +49 [0]681 302 70 258

www.clinicalpharmacy.me <http://www.clinicalpharmacy.me>

 


Received on Tue Jul 28 2015 - 02:07:56 EDT

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