Abstract:
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While randomization is a key part of research, randomization procedures often do not reflect best practices. In order to accelerate the delivery of high quality randomization schedules, we implement a stratified permuted block randomization system which includes: * A flexible spreadsheet based syntax to structure the randomization as a series of ‘superblocks’ within each strata, cohort, or combination, easing the use of best-practices such as variable block sizes, and relaxed or mixed permuted block methods; * Complete computational transparency, with an audit trail from parameters and random numbers through block selection and unit assignments, and implemented in open-source R code; * Simulations by default for testing, validation, or rerandomization analyses using pseudo-random number streams generated by the Wichmann-Hill 2006 algorithm for repeatable and independent parallel random number sequences; * Reporting functions to measure quality of generated schedules on metrics such as potential selection bias, treatment imbalance, and risk of under-enrolling strata. The resulting system allows rapid implementation, testing, validation and documentation.
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