RE: The Standard Two-Stage and ELS
Kim,
The first stage estimates are those calculated POSTHOC and output in the table.
Then you need to conduct stage two and conduct a sort of summary on the
parameters calculated in Stage I.
Maxeval =0 and the large OMEGA are just to avoid the POSTHOC being influenced
by the population value.
As a sensitivity you may want to try different values of Omega e.g: 1000 and
see how your individual PK parameters change.
Bests,
Samer
Quoted reply history
-----Original Message-----
From: [email protected] on behalf of Brian M. Sadler
Sent: Tue 3/3/2009 13:46
To: 'Kristensen, Kim'; [email protected]
Subject: RE: [NMusers] The Standard Two-Stage and ELS
Kim,
In the $ESTIMATION statement, you need to change MAXEVAL=0 to MAXEVAL=9999
(or some other non-zero integer) before the estimation process will proceed
beyond the initial estimates.
Cheers... Brian
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Kristensen, Kim
Sent: Tuesday, March 03, 2009 11:36 AM
To: Brian M. Sadler; [email protected]
Subject: RE: [NMusers] The Standard Two-Stage and ELS
Dear Brian
Thanks for the suggestion. I've tried changing the ID and the first row to
EVID=1. However, the posthoc (ELS) modelling of data, as suggested by Dr's
Beal and Shafer, dosn't seem to go through as the parameter are all left
unchanged i.e. as initial estimates!
/Kim
-----Original Message-----
From: Brian M. Sadler [mailto:[email protected]]
Sent: den 3 mars 2009 12:49
To: Kristensen, Kim; [email protected]
Subject: RE: [NMusers] The Standard Two-Stage and ELS
Dear Kim,
There is no ID variable in the $INPUT statement. Try:
$INPUT SUB=ID AMT TIME DV EVID CMT MDV
Cheers... Brian
Brian M. Sadler, Ph.D.
Strategic PK Consulting, LLC
1209 Seabrook Avenue
Cary, North Carolina 27511
USA
[email protected]
+1 (919) 523-5485 (mobile)
+1 (508) 408-0250 (fax)
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Kristensen, Kim
Sent: Tuesday, March 03, 2009 4:26 AM
To: [email protected]
Subject: [NMusers] The Standard Two-Stage and ELS
Dear user
Searching the user site I found a pre-published method by Dr's Beal and
Shafer (link given below) to do The Standard Two-Stage Estimation using ELS
with NONMEM. Out of curiosity I tried it, but I could not get it to work
with NM6. Could anyone tell what I do wrong?? Control stream and test data
are given below.
http://www.cognigencorp.com/nonmem/nmo/topic035.html
$PROBLEM Standard two stage
$INPUT SUB AMT TIME DV EVID CMT MDV
$DATA ASA_NM3.txt IGNORE=#
$SUBROUTINE ADVAN1 TRANS2
$PK
CL=THETA(1)*EXP(ETA(1))
V =THETA(2)*EXP(ETA(2))
$ERROR
Y=F+F*EXP(ETA(3))*ERR(1)
$THETA 5 50 ;these are rough typical population
values
$OMEGA 100 100 100
$SIGMA 1 FIXED
$ESTIMATION MAXEVAL=0 POSTHOC METH=COND INTERACTION
$TABLE SUB TIME CL V
# SUB AMT TIME DV EVID CMT MDV
1 650 0 0 4 1 1
1 . 1 98 . 1 0
1 . 2 82 . 1 0
1 . 4 58 . 1 0
1 . 8 33 . 1 0
1 . 12 22 . 1 0
1 . 15 17 . 1 0
1 . 20 12 . 1 0
1 . 30 7.5 . 1 0
1 . 45 3.7 . 1 0
1 . 60 1.8 . 1 0
1 . 70 1.2 . 1 0
2 650 0 0 4 1 1
2 . 1 101 . 1 0
2 . 2 85 . 1 0
2 . 4 57 . 1 0
2 . 8 33 . 1 0
2 . 12 22 . 1 0
2 . 15 17 . 1 0
2 . 20 12 . 1 0
2 . 30 7.5 . 1 0
2 . 45 3.7 . 1 0
2 . 60 1.8 . 1 0
2 . 70 1.1 . 1 0
________________________________
Kim Kristensen, M.Sc(pharm),Ph.D.
Pharmacokineticist,
Clinical Pharmacology & DMPK
Medical Science Sweden
AstraZeneca R&D Lund
SE-221 87 Lund, Sweden
Tel: +46 46 33 86 63 Fax: +46 46 336110
> Mobil: +46 (0) 705 33 77 18
> e-mail: [email protected]
________________________________