modeling steady state-con

From: alison@c255.ucsf.EDU (ABoeckmann) Subject: modeling steady state-con Date: 14 Nov 1997 23:45:46 -0500 RE: mail from Georgia Kollias: The doses in Georgia's data file are multiple transient infusions, not steady state doses (as PREDPP understands such doses). If she believes that they lead to steady-state, then she can describe them as SS doses this way: ------------------------------------ ID DOSE TIME DV RATE EVID SS ------------------------------------ 1 1.25 8 . 1.25 1 1 1 1.25 8 0.46 . . 0 1 1.25 15 . 1.25 1 1 1 1.25 15 0.48 . . 0 1 1.25 22 . 1.25 1 1 1 1.25 22 0.17 . . 0 1 2.50 29 . 2.50 1 1 1 2.50 29 0.90 . . 0 1 3.75 36 . 3.75 1 1 1 3.75 36 0.68 . . 0 ------------------------------------ Note that a type 1 ("reset") SS record is present at the same time as each observation, implying that dosing with this rate has been going on"forever", and therefor the calculations are be done using steady state formulas. I tried 2 little control streams, one for her original data, and one for the above, and got virtually the same predictions. I don't say that ADVAN1 is the right model for a transdermal patch - I am only looking at the dosing here. With Georgia's original data file: $PROB not $INPUT ID DOSE TIME DV AMT RATE ADDL II EVID $DATA datanotss $SUBR ADVAN1 $PK K=1 $ERROR Y=F+ETA(1) $TABLE TIME With the above data file: $PROB not $INPUT ID DOSE TIME DV RATE EVID SS $DATA datassx $SUBR ADVAN1 $PK K=1 $ERROR Y=F+ETA(1) $TABLE TIME