R/Transferdatatolist_Stopboundinf.R

In BayesianPlatformDesignTimeTrend: Simulate and Analyse Bayesian Platform Trial with Time Trend

#' @title Stopboundinf
#' @description This function summaries and checks stopping boundary information.
#' @param Stop.type The type of stopping boundary should be "Early-Pocock", "Early-OBF" and "Noearly". Default is "Early-Pocock" which is the Pocock boundary with early stopping.
#'
#' @param Boundary.type Whether the futility boundary and the efficacy boundary are the same conservative.
#'     Default is "Symmetric" which means they are as conservative as each other.
#'     Boundary.type = "Asymmetric" means that the efficacy boundary and the futility boundary are not as conservative as each other
#' @param cutoff = c(cutoff1, cutoff2). A numerical vector of cutoff value for each boundary.
#'     The first element is the efficacy boundary cutoff. The second element is the futility boundary cutoff
#'     Pr(theta_1 > theta_0|D_n) > cutoff1. Should input the cutoff1 for efficacy boundary as the first element
#'     Pr(theta_1 < theta_0|D_n) < cutoff2. Should input the cutoff2 for futility boundary as the first element
#'
#' @return The list of information required for boundary construction function 'Stopbound.inf'
#' @export
#'
#' @examples
#' Stop.type = "Early-Pocock" #(Pocock boundarty is a flat boundary across time)
#' Boundary.type = "Symmetric"
#' cutoff = c(0.9928, 0.0072)
#'
#' Stopbound.inf = Stopboundinf(Stop.type, Boundary.type, cutoff)
#' #Stopbound.inf
#' #$Stop.type
#' # [1] "Early-Pocock"
#' #$Boundary.type
#' #[1] "Symmetric"
#' #$cutoff
#' # [1] 0.9928 0.0072
#' @author Ziyan Wang
Stopboundinf = function(Stop.type="Early-Pocock", Boundary.type="Symmetric", cutoff=c(0.9928, 0.0072)) {
  if (Boundary.type == "Symmetric") {
    if (Stop.type == "Early-OBF" & cutoff[1] == cutoff[2]) {
      cutofftemp = cutoff
    }
    else if (sum(Stop.type == c("Early-Pocock","Noearly")) & sum(cutoff) == 1) {
      cutofftemp = cutoff
    }
    else{
      stop("Error: The input of cutoff should be Symmetric")
    }
  }
  else if (Boundary.type == "Asymmetric") {
    if (sum(Stop.type == c("Early-Pocock","Noearly")) & sum(cutoff) != 1) {
      cutofftemp = cutoff
    }
    else if (Stop.type == "Early-OBF" & cutoff[1] != cutoff[2]) {
      cutofftemp = cutoff
    }
    else{
      stop("Error: The input of cutoff should be Asymmetric")
    }
  }
  else {
    stop("Error: The boundary type is invalid. Should input Symmetric or Asymmetric.")
  }
  Stopbound.inf = list(
    Stop.type = Stop.type,
    Boundary.type = Boundary.type,
    cutoff = cutofftemp
  )
  return(Stopbound.inf)
}