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+# biomkrAccrual
+## Simulating recruitment at time of randomisation to adaptive trials with arm eligibility determined by biomarker status.
+
+The `{biomkrAccrual}` package uses a Poisson-Gamma-Dirichlet model to simulate
+trial recruitment for multi-site, multi-region, multi-arm trials. Recruitment per 
+site is modelled with the Poisson-Gamma model (Anisimov and Federov, 2007).
+A hierarchical Dirichlet model is used to model biomarker proportions for sites
+within regions. Recruitment to a given site in a given week is then randomised
+to biomarker status using the prevalences drawn from the Dirichlet model for that
+site.
+
+## Running a single simulation
+
+`biomkrAccrual()`
+
+The default settings will use the configuration files in the `extdata` directory, and will
+keep the resulting data files and recruitment plots. The location can be specified with 
+`output_path` and `figs_path`.
+
+## Running a set of simulations
+
+`biomkrAccrualSim(n = 250)`
+
+The datafiles and recruitment plots from the individual runs will not be kept (this
+can be changed with `quietly = FALSE`) but will preserve the summary datafiles and
+distribution plots.
+
+## Practical notes
+
+There are a very large number of arguments to both commands, and three configuation files,
+one of which (the relationship of treatment arms to biomarker recruitment arms) is a JSON.  
+This is because flexibility is required, and they are intended to be driven by a dashboard 
+in future.
+
+This package will not pass R CMD Check because it is written using the new object orientation 
+system for R, `{S7}`, and CMD Check does not yet understand the syntax.
+
+
+Anisimov, V.V., Fedorov, V.V., 2007. Modelling, prediction and adaptive adjustment of 
+recruitment in multicentre trials. Statistics in Medicine 26, 4958–4975. 
+https://doi.org/10.1002/sim.2956
+