Randomization in clinical studies
Chi-Yeon Lim, Junyong In, Chi-Yeon Lim, Junyong In
Abstract
Randomized controlled trial is widely accepted as the best design for evaluating the efficacy of a new treatment because of the advantages of randomization (random allocation). Randomization eliminates accidental bias, including selection bias, and provides a base for allowing the use of probability theory. Despite its importance, randomization has not been properly understood. This article introduces the different randomization methods with examples: simple randomization; block randomization; adaptive randomization, including minimization; and response-adaptive randomization. Ethics related to randomization are also discussed. The study is helpful in understanding the basic concepts of randomization and how to use R software.
Keywords: Adaptive randomization; Minimization; Random allocation; Randomization; Randomized controlled trial; Restrictive randomization; Simple randomization.
Conflict of interest statement
No potential conflict of interest relevant to this article was reported.
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Source: PubMed