Dear nonmemusers:
First I want to apologize because my lacks
of information when I ask for help making hard to all of you to understand what
I’m trying to do. When I wrote ”I also try to use the code that Nick send to me
but it did
not work", means I was not able to figure out how to relate DV in the
third conditional were I indicate the replacement of DV values, and replacement
in this case did not happen. Definition of IPRED was the missing part I did
not figure out before.
This
is my complete $ERROR code (IPRED is defined as Nick guessed):
$ERROR (OBSERVATION ONLY)
ADD = THETA(21) ; FROM IV ADMINISTRATION
IF (PLGA.EQ.1) ADD = THETA(22) ; Intramuscular FORMULATION 1
IF (PLGA.EQ.2) ADD = THETA(23) ; Intramuscular FORMULATION 2
IF (PLGA.EQ.3) ADD = THETA(24) ; Subcutaneous FORMULATION 3
LLOQ = LOG(0.020) ;LOW LIMIT OF QUANTIFICATION
IPRED = LOG(F)
IRES=DV-IPRED
W=ADD
IWRES=IRES/W
Y=IPRED+W*EPS(1)
IF (ICALL.EQ.4)THEN
;REQUIRED TO SIMULATE
IF (F.NE.0) Y=LOG(F)
IF(Y.LT.LLOQ)
THEN;REQUIRED TO REPLACE VALUES FOR LOQ
Y = LLOQ
ENDIF
ENDIF
Now I know the "LLOQ replace code" could be written also as:
IF (ICALL.EQ.4)THEN
;REQUIRED TO SIMULATE
IF (F.NE.0) Y=LOG(F)
IF(IPRED.LT.LLOQ)
THEN;REQUIRED TO REPLACE VALUES FOR LOQ
Y = LLOQ
ENDIF
ENDIF
Thank you very much for your help. Both codes work perfectly!
Elba
Date: Mon, 25 Apr 2011 21:26:15 +0200
From: [email protected]
To: [email protected]
Subject: Re: [NMusers] Replacement of values during simulation
Elba,
It's hard to understand what you are doing because you do not give
all the details e.g. how is IPRED computed? I am guessing it might
be LOG(F)?
In the ICALL.EQ.4 block it would be clearer (to me) if you wrote
the following:
IF (IPRED.LT.LLOQ) THEN
Y=LLOQ
ENDIF
What do you mean by "I also try to use the code that Nick send me
but it did not work"? What exactly happens? Why do you think it does
not work?
Nick
On 25/04/2011 8:08 p.m., elba romero wrote:
Dear Nathan
and Nick:
Thank you very
much for your help. Finally I'm exploring the model under this
conditions, and as Nathan explained before, I simulate the
effect of an LOQ in my resulting dataset. The final code is
this:
LLOQ
= LOG(0.020) ;LOW LIMIT OF QUANTIFICATION
Y=IPRED+W*EPS(1)
IF
(ICALL.EQ.4)THEN ;Required to simulate
IF
(F.NE.0) Y=LOG(F)
IF(Y.LE.LLOQ) THEN;Required to replace values lower or
equal than LOQ
Y
= LLOQ
ENDIF
ENDIF
This
instruction allow me to work with PsN and "play around" to
know my model. I also try to use the code that Nick send me
but it did not work. I wonder where is the problem, just to
close the circle...
Elba.
Date:
Sun, 24 Apr 2011 21:48:30 -0500
Subject:
Re: [NMusers] Replacement of values during simulation
From:
[email protected]
To:
[email protected]
CC:
[email protected]
Elba,
In the
$ERROR block you can add code such as the following:
Y=F +
F*ERR(1) + ERR(2)
; Replace
values below -3.9 with -3.0
IF(Y.LE.-3.9) THEN
Y=-3.0
ENDIF
This can
often be used to simulate the effect of an LOQ on the
resulting dataset.
Good luck!
Nathan
--
Nathan S.
Teuscher, PhD
Founder,
PK/PD Associates
www.learnpkpd.com
blog.learnpkpd.com
[email protected]
Twitter: www.twitter.com/learnpkpd
Facebook:
www.facebook.com/pages/Learn-PKPD
YouTube Channel: www.youtube.com/learnpkpd
On Sat, Apr 23, 2011 at 11:53 AM, elba
romero <[email protected]>
wrote:
Dear nonmemusers:
I’m performing some simulations in
order to verify the
behaviour of my model. My iDV and DV are time an
concentration respectively.
In my case it would be useful to
replace all simulated data
(DV) that have values less or equal than -3.9 by this
value: -3.0.
Does anybody could help me how to
give this instruction to
NONMEM7 in order to replace all this values during
simulation?
Thank you in advance!
Elba
PhD student
UNAV
--
Nick Holford, Professor Clinical Pharmacology
Dept Pharmacology & Clinical Pharmacology
University of Auckland,85 Park Rd,Private Bag 92019,Auckland,New Zealand
tel:+64(9)923-6730 fax:+64(9)373-7090 mobile:+64(21)46 23 53
email: [email protected]
http://www.fmhs.auckland.ac.nz/sms/pharmacology/holford
