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http://dx.doi.org/10.5351/KJAS.2010.23.6.1047

Comparing the Randomization Methods Considering the Covariates in a Clinical Trial  

Yu, A-Mi (Department of Statistics, Korea University)
Lee, Jae-Won (Department of Statistics, Korea University)
Publication Information
The Korean Journal of Applied Statistics / v.23, no.6, 2010 , pp. 1047-1056 More about this Journal
Abstract
In clinical trials, patients should be randomly allocated to treatment and control groups that consider the balance of their prognostic factors(covariates). There are many randomization methods and stratification is popular in Korea. In stratification, patients are divided into strata based on covariates and then the patients are randomly assigned to the arms of each strata. If the number of covariates increases then the number of strata increases rapidly and the results may not be reliable when the patients are inadequate in each strata. To complement this problem Pocock and Simon (1975) suggested a new randomization method that called for minimization focusing on the balance of covariates. In this study, we compare the advantages and disadvantages, the imbalance of covariates, the power of minimization, and other randomization methods by simulation.
Keywords
Randomization; minimization; prognostic factor; clinical trial;
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