This reduced piecewise exponential survival software implements the likelihood ratio test procedure in Han, Schell, and Kim (2012, 2014), and Han et al. (2016). Inputs to the program can be either times when events/censoring occur or the vectors of total time on test and the number of events. Outputs of the programs are times of events and the corresponding p- values. The order of times and p-values is determined by a backward elimination procedure. Details about the model and implementation are given in Han et al. 2014. Adelson (2016) also mentioned the application of the method. This program can run in R version 3.2.2 and above.
You can install RPEXE.RPEXT from github with:
# install.packages("devtools") devtools::install_github("hangangtrue/RPEXE.RPEXT")
This is a basic example which shows you how to solve a common problem:
require(RPEXE.RPEXT) #> Loading required package: RPEXE.RPEXT library(RPEXE.RPEXT) # load in the data2 dataset data(simple) times = simple[,2] cens = simple[,1] result = RPEXEv1_2(times,cens,monotone = 3,criticalp = 0.05) #>  "last" #>  9
Some more examples can be found in demos and vignettes of the package.
 Han, G., Schell, M. J., and Kim, J. (2012) “Comparing Two Exponential Distributions Using the Exact Likelihood Ratio Test," Statistics in Biopharmaceutical Research, 4(4), 348-356.
 Han, G., Schell, M. J., and Kim, J. (2014) “Improved Survival Modeling in Cancer Research Using a Reduced Piecewise Exponential Approach," Statistics in Medicine, 33(1), 59-73.
 Han, G., Schell, M., Zhang, H., Zelterman, D., Pusztai, L., Adelson, K., and Hatzis, C. (2016) “Testing Violations of the Exponential Assumption in Cancer Clinical Trials with Survival Endpoints," Biometrics, DOI: 10.1111/biom.12590; PMID: 27669414.
 Adelson, K. B., Ramaswamy, B., Sparano, J. A., Christos, P. J., Wright, J. J., Raptis, G., Han, G., Villalona-Calero, M., Ma, C., Hershman, D., Baar, J., Klein, P., Cigler, T., Budd, T., Novik, Y., Tan, A.R., Tannenbaum, S., Goel, A., Levine, E., Shapiro, C. L., Andreopoulou, E., Naughton, M., Kalinsky, K., Waxman, S., Germain, D. (2016) “Randomized Phase II Trial of Fulvestrant Alone or in Combination with Bortezomib in Hormone Receptor-Positive Metastatic Breast Cancer Resistant to Aromatase Inhibitors: A New York Cancer Consortium Trial," Nature Partner Journals Breast Cancer, Volume 2, Article ID 16037, DOI: 10.1038/npjbcancer.2016.37.