RE: M3 method and multiple LOQ values
Dear Rebecca,
I think you want to change
DUM=(LOQ-IPRED)
To
DUM=(LOQ-IPRED)/(SIG*IPRED)
BTW, with the new NONMEM version, the need to fix SIGMA to 1 is no longer
necessary as you can use SIGMA(1,1) on the right-hand side of expressions in
$ERROR
Your expression would then become
$ERROR
IPRED=F
LOQ=LLOQ
DUM=(LOQ-IPRED)/(SQRT(SIGMA(1,1))*IPRED)
CUMD=PHI(DUM)
IF (BQL.EQ.0) THEN
F_FLAG=0
Y=IPRED*(1+ ERR(1))
ENDIF
IF (BQL.EQ.1) THEN
F_FLAG=1
Y=CUMD
ENDIF
$EST METHOD=COND INTER LAPLACIAN
$SIGMA .1
Best regards,
Mats
Mats Karlsson, PhD
Professor of Pharmacometrics
Dept of Pharmaceutical Biosciences
Faculty of Pharmacy
Uppsala University
Box 591
75124 Uppsala
Phone: +46 18 4714105
Fax + 46 18 4714003
Quoted reply history
From: [email protected] [mailto:[email protected]] On
Behalf Of Rebecca N. Burns
Sent: 07 March 2013 17:46
To: [email protected]
Subject: [NMusers] M3 method and multiple LOQ values
All,
I am implementing the M3 method using NONMEM7.2. My error structure is
proportional. I have two questions regarding the control stream shown
below.
1. Is the control stream correct for a proportional error model?
2. Each DV has its own LOQ so I cannot give one LOQ value. I was
planning to assign a column in my data frame which defines LOQ for each DV.
Is this an appropriate approach?
Any input/advice would be much appreciated!
Thanks,
Rebecca Neal Burns, PharmD, PhD
Post-Doctoral Scholar, Pharmacometrics
Mercer University, Atlanta, GA
$ERROR
SIG=THETA(4)
IPRED=F
LOQ=LLOQ
DUM=(LOQ-IPRED)
CUMD=PHI(DUM)
IF (BQL.EQ.0) THEN
F_FLAG=0
Y=IPRED*(1+SIG*ERR(1))
ENDIF
IF (BQL.EQ.1) THEN
F_FLAG=1
Y=CUMD
ENDIF
$EST METHOD=COND INTER LAPLACIAN
$SIGMA 1 FIX