Review Article Randomization, What is the Proper Method? Jin Ho Hong, M.D., Jae Chul Yoo, M.D. Shoulder & Sports medicine, Department of Orthopedic Surgery, Samsung Medical Center Purpose: Among the numerous clinical researches and following articles, there are few cases that apply proper methodology, which guarantees high reliability. By understanding the right concept and randomization of proper methods, research bias could be minimized. Materials and Methods: By reviewing the recently published articles about randomization, the basic concept and the necessity of applying the technique was described. Then proper methodologies for good randomization such as simple randomization, permuted-block randomization, and stratification were briefly introduced with examples. Results and Conclusion: Randomization lowers the possibility of bias and leads to higher reliability in clinical research. To obtain more reliable research results, understanding the right concept and proposition of proper methodologies of randomization is essential for researchers. Key Words: Randomization, Random number, Selection bias, Stratification
Fig. 1. Coin flipper from Random.org.
Fig. 2. SNOSE method, Doig 2). Fig. 3. Imbalance of simple randomization, Kang 3). Fig. 4. Example of permuted block randomization, Doig 2).
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