Use the checkboxes to build the structural model equation.
Baseline: Check if the model has a baseline response. A new parameter, E0, is added to the baseline response and the Fractional checkbox is made available.
Check the Fractional box if the Emax model is fractional. Selecting this option modifies the E0 equation statement.
Inhibitory: Check if the model is inhibitory. The structural parameters EC50 and Emax change to IC50 (concentration producing 50% of maximal inhibition) and E0 (baseline effect).
Sigmoid: Check if the model is sigmoidal. A shape parameter, Gam, is added.
For a PK/Emax model type, the following settings become available:
Effect: Check this box to add an effect compartment (Ce) to the model (and an exit rate constant (Ke0), It represents an effect site for a PK/PD model with a delay between the central and effect-site concentrations, that is, plots of plasma concentration versus effect level show a counter-clockwise hysteresis.
Freeze PK freezes the standard deviation to the value shown in the StDev field and prevents estimation of the PK part of the model.