Non-proportional hazard (NPH) is commonly observed in immuno-oncology studies, where the survival curves of the treatment and control groups show delayed separation. To properly account for NPH, several statistical methods have been developed. One such method is Max-Combo test, which is a straightforward and flexible hypothesis testing method that can simultaneously test for constant, early, middle, and late treatment effects. However, the majority of the Max-Combo test performed in clinical studies are unstratified, ignoring the important prognostic stratification factors. To fill this gap, we have developed an R package for stratified Max-Combo testing that accounts for stratified baseline factors. Our package explores various methods for calculating combined test statistics, estimating joint distributions, and determining the p-values.

Provides exact analytical algorithms for computing optimum sample
  allocations in stratified sampling.
  Supports classical Neyman-Tschuprow allocation, minimum-cost allocation under
  a variance constraint, and multi-domain allocation with controlled precision.
  Handles lower and upper bounds, cost constraints, and multiple domains.
  Includes helper functions for variance computation, allocation summaries,
  rounding, and example datasets for testing and benchmarking.

A pilot matching design to automatically 
    stratify and match large datasets.  The manual_stratify() function allows
    users to manually stratify a dataset based on categorical variables of 
    interest, while the auto_stratify() function does automatically by
    allocating a held-aside (pilot) data set, fitting a prognostic score  
    (see Hansen (2008) <doi:10.1093/biomet/asn004>) on the pilot set, and stratifying the data set based
    on prognostic score quantiles.  The strata_match() function then does optimal
    matching of the data set in parallel within strata.

Offers a comprehensive approach for analysing stratified 2x2 contingency tables. It facilitates the calculation of odds ratios, 95% confidence intervals, and conducts chi-squared, Cochran-Mantel-Haenszel, Mantel-Haenszel, and Breslow-Day-Tarone tests. The package is particularly useful in fields like epidemiology and social sciences where stratified analysis is essential. The package also provides interpretative insights into the results, aiding in the understanding of statistical outcomes.