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A SAS macro for constrained randomization of group-randomized designs.

M Ashraf Chaudhary·Lawrence H Moulton
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Abstract

Group-randomized study designs are useful when individually-randomized designs either are not possible, or will not be able to estimate the parameters of interest. Group-randomized trials often have small number of experimental units or groups and strong geographically-induced between-unit correlation, thereby increasing the chance of obtaining a "bad" randomization outcome. It has been suggested to highly constrain the design through restriction to those allocations that meet specified criteria based on certain covariates available at the baseline. We describe a SAS macro that allocates treatment conditions in a two-arm stratified group-randomized design that ensures balance on relevant covariates. The application of the macro is illustrated using two examples of group-randomized designs.

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AIDS VaccinesAIDS-Related Opportunistic InfectionsCounselingHIV InfectionsHumansRandom AllocationRandomized Controlled Trials as TopicSoftwareTuberculosisJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov't

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M Ashraf Chaudhary, Lawrence H Moulton. 2006-07-25. A SAS macro for constrained randomization of group-randomized designs.. https://doi.org/10.1016/j.cmpb.2006.04.011

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