Hi Benjamin,
You should not use the closed form code for a linear model to disease
progression if the slope is varying with time. See slide 9:
http://holford.fmhs.auckland.ac.nz/docs/clinical-pharmacology-equals-disease-progress-plus-drug-action.pdf
In your case the slope is dependent on WCMI
Sorry, there was a typos in the code, here is the version with
continuous SLOPE function
IF(CONC.LE.THRESH) SLOPE = THETA(3)+THETA(4)*CONC+ETA(2)
IF(CONC.GT.THRESH) SLOPE =
THETA(3)+THETA(4)*THRESH+THETA(5)*(CONC-THRESH)+ETA(2)
Then, if you rename
NEWTHETA3 = THETA(3)+THETA(4)*THRESH
you will
Benjamin.
Even as WCMIN is continuous by nature, it is not continuous in the
dataset (at observation points). You may look at your WCMIN values in
the data file (I assume this values are in the data file?) and see where
the initial conditions for THETA(1) placed in that range. Step for
gradien
Hi Leonid. Thanks for your quick response. WCMIN is continuous. In fact, it is
actually identical to CONC (forgot to change it while simplifying). Any
thoughts on this?Ben
- Originalnachricht -
Von: Leonid Gibiansky [mailto:lgibian...@quantpharm.com]
Gesendet: Thursday, September 19, 201
