r2rtf
The clinical-report table engine learned Chinese, then learned to leave RTF entirely
Comparison · Analytics
simtrial vs spiro
A side-by-side editorial comparison of simtrial and spiro — release velocity, themes, recent moves, and the top alternatives to consider.
simtrial vs spiro: at a glance
What is simtrial?
A fixed-design trial simulator grew a pluggable test framework, then spent a year proving the numbers
simtrial simulates time-to-event clinical trials and applies the tests used to analyse them — logrank, weighted logrank, MaxCombo, RMST, milestone. The 0.4.0 release turned it from a fixed-sample simulator into a group sequential one and standardised every test behind a common output contract, and the releases since have been about making that machinery correct and fast enough to run at scale. Version 1.0.0 arrived in June 2025 with the API settled and three vignettes explaining both the one-call and build-it-yourself paths.
What is spiro?
Cardiopulmonary exercise test data in R, one metabolic cart vendor at a time.
spiro imports and processes cardiopulmonary exercise testing data in R, handling the file formats that metabolic carts from Cosmed, Cortex, Vyntus, and ZAN emit, then interpolating, smoothing, and summarizing them into comparable variables. The bulk of ongoing work is vendor format compatibility rather than analysis features — 0.2.4 fixed Cosmed imports failing in rare cases and Cortex imports on newer devices, and 0.2.2 added English-language Vyntus files after 0.1.2 added French ones. The analysis side, spiro_max(), spiro_smooth() and spiro_plot(), has been stable for some time.
simtrial vs spiro: editorial side-by-side
simtrial
0.0ANALYTICS
A fixed-design trial simulator grew a pluggable test framework, then spent a year proving the numbers
◆ Current state
simtrial simulates time-to-event clinical trials and applies the tests used to analyse them — logrank, weighted logrank, MaxCombo, RMST, milestone. The 0.4.0 release turned it from a fixed-sample simulator into a group sequential one and standardised every test behind a common output contract, and the releases since have been about making that machinery correct and fast enough to run at scale. Version 1.0.0 arrived in June 2025 with the API settled and three vignettes explaining both the one-call and build-it-yourself paths.
◆ Where it's heading
Post-1.0 the work is almost entirely statistical correctness and speed, and it is concentrated in sim_gs_n(): one-sided efficacy bounds, stratified targeted-event cut dates, a helper that derives cuttings straight from the design object. Performance moves in one direction throughout — dplyr replaced by data.table, foreach combination replaced by manual assembly, parallelisation added to sim_fixed_n() — because simulation-based operating characteristics are only useful if you can afford enough replications.
◆ Prediction
The recent fixes cluster on stratified and group sequential paths, so the next release most likely continues there rather than adding a new test type. The cut_from_design() helper suggests tighter coupling to gsDesign2 design objects is the direction of travel.
spiro
0.0ANALYTICS
Cardiopulmonary exercise test data in R, one metabolic cart vendor at a time.
◆ Current state
spiro imports and processes cardiopulmonary exercise testing data in R, handling the file formats that metabolic carts from Cosmed, Cortex, Vyntus, and ZAN emit, then interpolating, smoothing, and summarizing them into comparable variables. The bulk of ongoing work is vendor format compatibility rather than analysis features — 0.2.4 fixed Cosmed imports failing in rare cases and Cortex imports on newer devices, and 0.2.2 added English-language Vyntus files after 0.1.2 added French ones. The analysis side, spiro_max(), spiro_smooth() and spiro_plot(), has been stable for some time.
◆ Where it's heading
This is a mature rOpenSci package whose remaining work is dictated by other people's file formats. Each device firmware revision, each regional language variant, and each ggplot2 release generates maintenance, and that is what fills the changelog. The API itself settled early, with the 0.1.0 rOpenSci review pass renaming the protocol helpers to the pt_* prefix and 0.2.0 replacing the confusingly named spiro_import() with spiro_raw().
◆ Prediction
Expect the pattern to continue: import fixes as vendor formats shift and periodic plotting updates tracking ggplot2, with no indication of new analysis capability.
Alternatives to simtrial and spiro
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 simtrial or spiro.
DoseFinding
New stewardship at openpharma, then two releases adding the methods MCP-Mod was missing
webmockr
The stubbing library added httr2 support, then spent a year cutting itself free of everything else
crul
crul took mocking back from webmockr and made it a property of the client itself
dendroNetwork
Six releases, six identical bodies — the feed carries the package abstract instead of release notes
chattr
chattr deleted every LLM integration it had written and outsourced the lot to ellmer
See all simtrial alternatives → · See all spiro alternatives →
Recent activity from simtrial and spiro
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 1mo agospiroCosmed and Cortex import fixes for newer devices
- 8mo agosimtrialOne-sided efficacy bound and stratified cut date corrected
- 11mo agosimtrialsim_gs_n moved to data.table; stratified design example added
- 1y agosimtrial1.0.0 settles the wlr interface and documents both simulation paths
- 1y agospiroEnglish-language Vyntus files supported
- 1y agosimtrialMilestone Z-score denominator corrected; parallel sim_fixed_n arrives
- 2y agosimtrialChecks pass without Suggests dependencies
- 2y agosimtrialRMST and milestone tests, plus a user-definable cut and test framework ⚡
- 3y agospiroR-devel compatibility and data frame printing fix
- 3y agospirospiro_raw() replaces the misleading spiro_import()
- 3y agospiroFrench Vyntus support and protocol duration control
- 3y agospirospiro 0.1.1
Frequently asked questions
What is the difference between simtrial and spiro?
They serve adjacent needs but don't currently overlap on shipped themes. simtrial and spiro are shipping at a similar cadence (velocity 0.0 vs 0.0, both within Sparkpulse's "active" band). See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is simtrial better than spiro?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. simtrial and spiro are shipping at a similar cadence (velocity 0.0 vs 0.0, both within Sparkpulse's "active" band). For your specific use case, the alternatives sections above list other Analytics products to evaluate alongside.
What are the best alternatives to simtrial?
Top simtrial alternatives in Analytics are ranked by recent ship velocity. Browse the "simtrial alternatives" section above for the current picks, or visit /alternatives/simtrial for the full list with editorial commentary on each.
What are the best alternatives to spiro?
Top spiro alternatives in Analytics are ranked by recent ship velocity. Browse the "spiro alternatives" section above for the current picks, or visit /alternatives/spiro for the full list with editorial commentary on each.