gsDesign2 1.1.9

New features

• The minimal risk weighting strategy has been added to gs_design_rd() and gs_power_rd() for risk difference design (#611, #614, thanks to @LittleBeannie).
• The sequential_pval() function has been added to calculate the sequential p-value for an AHR group sequential design (#605, thanks to @LittleBeannie).
• The gs_cp() and gs_cp_simple() functions are now available for conditional power computation for AHR designs with non-constant effect size (#550, thanks to @LittleBeannie and @shiyuskaya).

Bug fixes

• The minor formula mistakes in gs_info_rd() have been corrected (#615, thanks to @LittleBeannie).
• The text summary of a stratified design now reports the correct enrollment duration and hazard ratios (#617, #619, thanks to @jdblischak).
• The updated design summary no longer reports the Time column (#622, thanks to @LittleBeannie).
• The change point used in the expected accrual calculation has been updated (#628, thanks to @LittleBeannie).

Improvements

• gs_design_ahr() has been optimized to be about 2x faster (#623, thanks to @yihui).
• Return object preparation from gs_power_npe() has been optimized (#624, thanks to @jdblischak).

Documentation

• The README example has been corrected to use the proper test_upper value (#621, thanks to @LittleBeannie).

Testing

• Developer and independent tests have been migrated from testthat to testit (#625, thanks to @yihui).
• Test names and tolerances have been updated for cross-platform consistency (#637, #639, thanks to @jdblischak).
• GitHub Actions workflows have been updated for Node 24, Codecov v6, and automated action updates (#626, #632, #633, #634, thanks to @jdblischak).