Erratum: Randomization in clinical studies (Korean J Anesthesiol, (2019), 72, 3, (221-232), 10.4097/kja.19049)

The Appendix of this article contained an error throughout in which an incorrect symbol was used for the assignment: it should be <-characters (which is the gets arrow in R), and not ← symbol in the command lines. For example, the corrected command lines are as below: (Formula Presented). The authors would like to apologize for any inconvenience caused.