Subpopulation Treatment Effect Pattern Plot (STEPP) A method to explore the treatment-covariate interactions in survival data arising from two treatment arms of a clinical trial. A permutation distribution approach to inference is implemented, based on permuting the covariate values within each treatment group. Software Depends: cmprsk, survival, splines Wai-ki Yip <wkyip@hsph.harvard.edu> Wai-ki Yip <wkyip@hsph.harvard.edu>, with contributions from Ann Lazar, David Zahrieh, Chip Cole, Ann Lazar, Marco Bonetti, and Richard Gelber GPL (>= 2) 2011-05-23 application/tgz http://CRAN.R-project.org/package=stepp