r2rtf
The clinical-report table engine learned Chinese, then learned to leave RTF entirely
A side-by-side editorial comparison of gsDesign2 and slider — release velocity, themes, recent moves, and the top alternatives to consider.
Group sequential design tooling that now monitors for harm, not just efficacy and futility.
gsDesign2 is the Merck-authored R package for group sequential clinical trial design under non-proportional hazards, and it has spent the last two years filling in the statistical surface its predecessor gsDesign established. Recent releases added conditional power (gs_cp, gs_cp_npe), sequential p-values, risk-difference designs with minimal risk weighting, and boundary updates from blinded interim estimates. Version 1.2.0 adds harm boundaries across the AHR and NPE design and power functions, wired through every summary and table export path.
Feature-complete since 2021, and every release since has been paying CRAN's C API bill
slider provides sliding-window and index-aware window functions for R, with a C implementation underneath and a specialised fast path for common aggregations. The user-facing surface has been stable since 0.3.0 in late 2022. Everything after that is compliance and platform work: STRING_PTR removed in 0.3.2, OBJECT() removed in 0.3.3, a vctrs callable's C signature corrected, and the minimum R version raised twice.
gsDesign2 is the Merck-authored R package for group sequential clinical trial design under non-proportional hazards, and it has spent the last two years filling in the statistical surface its predecessor gsDesign established. Recent releases added conditional power (gs_cp, gs_cp_npe), sequential p-values, risk-difference designs with minimal risk weighting, and boundary updates from blinded interim estimates. Version 1.2.0 adds harm boundaries across the AHR and NPE design and power functions, wired through every summary and table export path.
The package is converging on parity with gsDesign while extending past it — each release either closes a gap against the older package or adds a boundary type gsDesign never had. A visible second track is output plumbing: every new statistical feature now arrives already threaded through summary(), gs_bound_summary(), as_gt(), and as_rtf(), which is what regulatory submission work actually consumes. Performance work is steady but secondary, with gs_design_ahr() roughly 2x faster in 1.1.9.
Expect the harm boundary work to propagate into the WLR and risk-difference design families, which are the two design branches 1.2.0 left untouched, along with a vignette bridging harm boundaries to the remaining gsDesign test types.
slider provides sliding-window and index-aware window functions for R, with a C implementation underneath and a specialised fast path for common aggregations. The user-facing surface has been stable since 0.3.0 in late 2022. Everything after that is compliance and platform work: STRING_PTR removed in 0.3.2, OBJECT() removed in 0.3.3, a vctrs callable's C signature corrected, and the minimum R version raised twice.
Two forces set the release schedule, and neither is feature demand. The first is CRAN closing off non-API C entry points, which packages reaching into R internals for speed have to unwind one accessor at a time — slider is on its second such release with no visible loss of function. The second is vctrs, whose breaking changes slider absorbs ahead of time; 0.2.2 exists solely to prepare for one. The last release that added anything callers can see was 0.3.0's slider_plus() and slider_minus() extension hooks.
Expect the pattern to continue: another non-API accessor removal or a vctrs compatibility release, rather than new window functions. The C-level surface is the only part of this package still moving.
Other Analytics products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either gsDesign2 or slider.
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Six releases, six identical bodies — the feed carries the package abstract instead of release notes
chattr deleted every LLM integration it had written and outsourced the lot to ellmer
See all gsDesign2 alternatives → · See all slider alternatives →
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
They serve adjacent needs but don't currently overlap on shipped themes. gsDesign2 is currently shipping more aggressively (velocity 3.8 vs 0.0), with 1 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. gsDesign2 is currently shipping more aggressively (velocity 3.8 vs 0.0), with 1 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Analytics products to evaluate alongside.
Top gsDesign2 alternatives in Analytics are ranked by recent ship velocity. Browse the "gsDesign2 alternatives" section above for the current picks, or visit /alternatives/gsdesign2 for the full list with editorial commentary on each.
Top slider alternatives in Analytics are ranked by recent ship velocity. Browse the "slider alternatives" section above for the current picks, or visit /alternatives/slider for the full list with editorial commentary on each.