Hello
I have a doubt about the simulations about the covariates.
First situation: if my final model does not include any covariate, does it make any sense to do a simulations including different values of covariates?
Second situation: in my model I have only included body weight and serum creatinine but in my original csv.file there are many other covariates.
If I want only to simulate with different body weights and I want to fix other covariables, do I have to fix only serum creatinine (because it is the only included in the model file) or all them?
Third situation: I tried to fix all covariates excepte serum creatinine that was included in the model but when I looked at the simulations of the parameter values I observed that different values of age, gender were simulated in the 1000 simulated cases. Is that correct? In addition, the simulated values were very strange (gender values between 0 and 1, negative values for c-reactive protein)
Thanks!!!
Sonia