Hi all, could you help me explain how to calculate the percentage of explained and unexplained variability in IIV that has been reported in many publications?
example see this paper *Evaluation of covariate effects on pharmacokinetics of monoclonal antibodies in oncology (nih.gov)
for example if final model Volumn is calculated in this way:
V = tvV*exp(nV) * (WT/medianWT)^dVdWT * (AGE/medianAGE)^dVdAGE
if tvV=2
exp(nV) = 0.7
(WT/medianWT)^dVdWT for a median WT is 0.2
(AGE/medianAGE)^dVdAGE for a median AGE is 0.1
The explained variability by percentage is (0.2+0.1)/(0.2+0.1+0.7) = 30%?
and unexplained by 70%
is that correct?
Then how to account for a categorical factor ie. gender?
Edited by joybaker, 23 May 2023 - 09:17 AM.