Dear Beginner,
I faced the similar problem while simulating the concentrations using simulation mode. The concentrations are similar in each subject (also found some times the concentrations are negative at the last time points).
I tried predictive check option and i could not find any change in the concentration (i.e no variability in the simulations).
Did u try the predictive check option for simulating the plasma concentration proofiles ???????/
This is how I simulated the Oral plasma concentration profile:
01) Generated dataset listing ID (1 to 50), same dose (10 mg) and time points (1 to 24hr)
02) Chose PK model - 1 compartment extravascular. Allowed residual error Stdev value (eg. additive, 1.0) on the structure tab
On parameter--fixed effect tab, entered estimated values (human predicted values from rat and dog),
In random effect tab, leave random effect (eg, 0.3, 0.3 for nV and nCl as in final model)
Run options-- predictive check, and in selected a table to simulate the data.
The final output is same concentrations in all the subjects.
Can u help me if u tried this / solved the problem ???
There were some posts on predictive check but i didnt really understood them.
Thanks with best regards,
Raghav.