NM mixture model with three subgroups
From: "Tzeng, Tsang-Bin" Tsang-Bin.Tzeng@astrazeneca.com
Subject: [NMusers] NM mixture model with three subgroups
Date: Sun, 18 Dec 2005 09:22:47 -0500
Anyone has experience to extend the NONMEM mixture model in clearance from a
two-subgroup (bimodality, as shown below) one to a three-subgroup one. We
are currently working on a drug with polymorphism in metabolism (a primary
elimination pathway) and three subgroups (ultrafast, extensive, and slow
metabolism) have been identified either from previous work or from the
histogram plot of the current data. Thanks!
; MIXTURE MODEL
EST = MIXEST
POP1 = 0
POP2 = 0
IF (MIXNUM.EQ.1) THEN
POP1 = 1
ELSE
POP2 = 1
ENDIF
CL = POP1*CL1 +POP2*CL2
$MIX
P(1) =THETA(8)
P(2) =1-THETA(8)
NSPOP = 2
Sincerely yours,
Tsang-Bin Tzeng, Ph.D.
AstraZeneca Pharmaceuticals
(302) 885-9954