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[Experimental]

DualEndpointEmax is the class for the dual endpoint model with Emax function for dose-biomarker relationship.

Usage

DualEndpointEmax(E0, Emax, ED50, ref_dose_emax = 1, ...)

.DefaultDualEndpointEmax()

Arguments

E0

(numeric)
either a fixed number or the two uniform distribution parameters.

Emax

(numeric)
either a fixed number or the two uniform distribution parameters.

ED50

(numeric)
either a fixed number or the two uniform distribution parameters.

ref_dose_emax

(number)
the reference dose \(x*\) (strictly positive number). Note that this is different from the ref_dose in the inherited DualEndpoint model).

...

parameters passed to DualEndpoint().

Details

This class extends the DualEndpoint class so that the dose-biomarker relationship \(f(x)\) is modelled by a parametric Emax function: $$f(x) = E0 + [(Emax - E0) * (x/x*)]/[ED50 + (x/x*)],$$ where \(x*\) is a reference dose, \(E0\) and \(Emax\) are the minimum and maximum levels for the biomarker, and \(ED50\) is the dose achieving half of the maximum effect \(0.5 * Emax\). All parameters can currently be assigned uniform distributions or be fixed.

Slots

E0

(numeric)
either a fixed number or the two uniform distribution parameters.

Emax

(numeric)
either a fixed number or the two uniform distribution parameters.

ED50

(numeric)
either a fixed number or the two uniform distribution parameters.

ref_dose_emax

(positive_number)
the reference dose \(x*\) (note that this is different from the ref_dose in the inherited DualEndpoint model).

Note

Typically, end users will not use the .DefaultDualEndpointEmax() function.

Examples

my_model <- DualEndpointEmax(
  mean = c(0, 1),
  cov = matrix(c(1, 0, 0, 1), nrow = 2),
  sigma2W = c(a = 0.1, b = 0.1),
  rho = c(a = 1, b = 1),
  E0 = c(0, 100),
  Emax = c(0, 500),
  ED50 = c(10, 200),
  ref_dose_emax = 1000
)