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 From: owner-nmus...@globomaxnm.com [mailto:owner-nmus...@globomaxnm.com] On Behalf Of Rebecca N. Burns Sent: 07 March 2013 17:46 To: nmusers@globomaxnm.com 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
