Yu, Su-Been
Song, Bong-Gyu
Cheon, Kyeong-Jun
Kim, Ju-Won
Kim, Young-Hee
Yang, Byoung-Eun
Article History
Received: 29 March 2018
Accepted: 2 August 2018
First Online: 10 September 2018
Ethics approval and consent to participate
: The study was reported to the Regional Ethical Committee. They found that the study did not require approval because it is a study of existing literature, not a human-related study, and does not use human-related materials for research.
: No person’s data was used in this study.
: The authors declare that they have no competing interests.
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