get_par: Parameter Configuration for Endpoints and Comparators

In SimTOST: Sample Size Estimation for Bio-Equivalence Trials Through Simulation

Parameter Configuration for Endpoints and Comparators

Description

Constructs and returns a list of key parameters (mean vectors, variance-covariance matrices, and allocation rates) required for input into the sampleSize function. This function ensures that the parameters for each endpoint and comparator are consistent, properly named, and formatted.

Usage

get_par(
  mu_list,
  varcov_list,
  TAR_list,
  type_y = NA,
  arm_names = NA,
  y_names = NA
)

Arguments

mu_list	A list of mean (\mu) vectors. Each element in the list represents a comparator, with the corresponding \mu vector having a length equal to the number of endpoints.
varcov_list	A list of variance-covariance matrices. Each element corresponds to a comparator, with a matrix of size (n \times n), where n is the number of endpoints.
TAR_list	A list of treatment allocation rates (TARs) for each comparator. Each element contains a numeric value (can be fractional or integer) representing the allocation rate for the respective comparator.
type_y	A numeric vector specifying the type of each endpoint. Use 1 for primary endpoints and 2 for secondary or other endpoints.
arm_names	(Optional) A character vector containing names of the arms. If not provided, default names (e.g., T1, T2, ...) will be generated.
y_names	(Optional) A character vector containing names of the endpoints. If not provided, default names (e.g., y1, y2, ...) will be generated.

Value

A named list with the following components:

mu

A list of mean vectors, named according to arm_names.

varcov

A list of variance-covariance matrices, named according to arm_names.

tar

A list of treatment allocation rates (TARs), named according to arm_names.

type_y

A vector specifying the type of each endpoint.

weight_seq

A weight sequence calculated from type_y, used for endpoint weighting.

y_names

A vector of names for the endpoints, named as per y_names.

#' @details This function ensures that all input parameters (mu_list, varcov_list, and TAR_list) are consistent across comparators and endpoints. It performs checks for positive semi-definiteness of variance-covariance matrices and automatically assigns default names for arms and endpoints if not provided.

Examples

mu_list <- list(c(0.1, 0.2), c(0.15, 0.25))
varcov_list <- list(matrix(c(1, 0.5, 0.5, 1), ncol = 2), matrix(c(1, 0.3, 0.3, 1), ncol = 2))
TAR_list <- list(0.5, 0.5)
get_par(mu_list, varcov_list, TAR_list, type_y = c(1, 2), arm_names = c("Arm1", "Arm2"))

SimTOST documentation built on April 3, 2025, 9:05 p.m.