Tools for blinded sample size re-estimation (BSSR) in two-arm clinical trials with binary endpoints, together with the exact power and sample size calculations that the re-estimation relies on. Five exact statistical tests are implemented: Pearson chi-squared, Fisher exact, Fisher mid-p, Z-pooled exact unconditional, and Boschloo exact unconditional. Each test is available with a one-sided or a two-sided alternative, and the exact unconditional tests can be combined with the Berger-Boos procedure. Sample sizes can be re-estimated either at the planning stage, to study the operating characteristics of a design, or from the blinded data of a trial that is under way. Statistical methods based on Mehrotra et al. (2003) <doi:10.1111/1541-0420.00051>, Berger and Boos (1994) <doi:10.1080/01621459.1994.10476836> and Kieser (2020) <doi:10.1007/978-3-030-49528-2_21>.
| Version: | 2.0.0 |
| Depends: | R (≥ 3.5.0) |
| Imports: | fpCompare, ggplot2 (≥ 3.4.0), Rcpp, stats, utils |
| LinkingTo: | Rcpp |
| Suggests: | testthat (≥ 3.0.0), knitr, rmarkdown, Exact, exact2x2, microbenchmark |
| Published: | 2026-08-20 |
| DOI: | 10.32614/CRAN.package.bbssr |
| Author: | Gosuke Homma [aut, cre] |
| Maintainer: | Gosuke Homma <my.name.is.gosuke at gmail.com> |
| BugReports: | https://github.com/gosukehommaEX/bbssr/issues |
| License: | MIT + file LICENSE |
| URL: | https://github.com/gosukehommaEX/bbssr |
| NeedsCompilation: | yes |
| Language: | en-GB |
| Materials: | NEWS |
| CRAN checks: | bbssr results |
| Reference manual: | bbssr.html , bbssr.pdf |
| Vignettes: |
Re-estimating the Sample Size from Interim Data (source, R code) Introduction to bbssr (source, R code) Statistical Methods in bbssr (source, R code) Validation of bbssr (source, R code) |
| Package source: | bbssr_2.0.0.tar.gz |
| Windows binaries: | r-devel: bbssr_1.0.2.zip, r-release: bbssr_1.0.2.zip, r-oldrel: bbssr_1.0.2.zip |
| macOS binaries: | r-release (arm64): bbssr_1.0.2.tgz, r-oldrel (arm64): bbssr_1.0.2.tgz, r-release (x86_64): bbssr_1.0.2.tgz, r-oldrel (x86_64): bbssr_1.0.2.tgz |
| Old sources: | bbssr archive |
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