R/cutData.R

In keaven/simtrial: Clinical Trial Simulation

#  Copyright (c) 2022 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved.
#
#  This file is part of the simtrial program.
#
#  simtrial is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
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#' @importFrom  dplyr filter mutate select %>%
NULL

#' Cut a Dataset for Analysis at a Specified Date
#'
#' @param x a time-to-event dataset, e.g., generated by \code{simPWSurv}
#' @param cut_date date relative to start of randomization (\code{cte} from input dataset)
#' at which dataset is to be cut off for analysis
#'
#' @return A dataset ready for survival analysis
#'
#' @examples
#' # Use default enrollment and event rates and
#' # cut at calendar time 5 after start of randomization
#' library(dplyr)
#' sim_pw_surv(n = 20) %>% cut_data_by_date(5)
#'
#' @export
#'

cut_data_by_date <- function(x, cut_date){


  ans <- x %>%
    filter(enroll_time <= cut_date) %>%
    mutate(tte = pmin(cte, cut_date) - enroll_time,
           event = fail * (cte <= cut_date)) %>%
    select(tte, event, Stratum, Treatment)

  return(ans)
}