permGS is an R package implementing permutational group-sequential tests for time-to-event data based on the two-sample (weighted) log-rank test statistic. It supports exact permutation test when the censoring distributions are equal in the treatment and the control group and approximate imputation-permutation methods when the censoring distributions are different. One- and two-sided testing is possible.
Get the released version from CRAN:
Or the development version from github:
# install.packages("devtools") devtools::install_github("mbrueckner/permGS")