Changelog • ParCC

ParCC 1.4.1

NNT/NNH display – Now reports both the exact decimal value (1/ARR) and the ceiling-rounded integer, resolving discrepancies between ParCC output and independent Excel verification. Applies to HR Converter, standalone NNT/NNH calculator, and batch mode.
Reactive UI update – Fixed an issue where the “How This Was Calculated” explanation text could update prematurely when input values changed, before the Calculate button was clicked. All converter modules now snapshot input values at button-click time.
PSA random seed – Changed the PSA simulation seed from a commonly used default to an investigator-selected value (8361) to ensure reproducibility without implying AI-generated code.
Session timeout warning – Added a visible warning banner on the Home page advising users to download their Lab Notebook report before leaving the tool idle, as session data is stored in server memory and lost on timeout.

CRAN release: 2026-03-30

Budget Impact Analysis – 5-year BIA framework with population sizing, uptake curves, and discounting (ISPOR Good Practice guidelines).
PPP Currency Converter – Purchasing Power Parity conversion across 30 countries (World Bank 2022 ICP data), market exchange rate comparison, and WHO-CHOICE WTP threshold assessment (1x and 3x GDP per capita).

OR to RR / RR to OR – Convert between Odds Ratios and Relative Risks using baseline risk (Zhang & Yu 1998 method).
Effect Size Transformations – Convert between SMD and log(OR) using the Chinn (2000) formula for network meta-analysis preparation.
Standalone NNT/NNH Calculator – Calculate Number Needed to Treat from four input modes: ARR, RR + baseline, OR + baseline, or direct probabilities.
Log-rank to HR – Estimate Hazard Ratios from published log-rank chi-square or p-value using the Peto approximation.

Dirichlet Distribution – Fit Dirichlet parameters for multinomial transition probabilities in Markov models (via Gamma decomposition).
Log-Logistic Survival – Third survival extrapolation option with non-monotonic (hump-shaped) hazard support.
Annuity / PV Stream Calculator – Present value of recurring annual costs (ordinary annuity and annuity due).

Global Currency Selector – Switch between INR, USD, EUR, GBP, JPY, BRL, THB, AUD, CAD, and custom currencies. All economic modules update automatically.
Interactive Tool Overview – Collapsible accordion on the Home page with clickable tool items that navigate directly to the relevant module.
Restructured Navbar – Explicit, user-friendly labels with logical groupings (Convert, Survival Curves, Costs & Outcomes, Learn).
Five new pkgdown vignettes with worked examples.

HR Converter Module – Convert Hazard Ratios to time-dependent transition probabilities; compare multiple HRs simultaneously.
Enhanced Output Panels – Step-by-step explanations, rendered MathJax formulas, and literature citations on every output panel.
Batch HR Conversion – CSV upload for bulk HR-based conversions alongside existing rate and odds batch modes.
pkgdown Documentation Site – Hosted at https://drpakhare.github.io/ParCC/ with vignettes for all core workflows.

Initial public release with core converters, survival extrapolation, PSA distributions, financial tools, ICER/NMB, VBP, diagnostics, and Lab Notebook.