Yeom, Yoo Kyung
Chae, Eun Young http://orcid.org/0000-0002-3478-6721
Kim, Hak Hee
Cha, Joo Hee
Shin, Hee Jung
Choi, Woo Jung
Article History
Received: 27 September 2018
Accepted: 27 December 2018
First Online: 5 January 2019
Ethics approval and consent to participate
: This study was approved by the institutional review board of Asan Medical Center (No. 2017–0440), and the need for informed consent was waived due to the retrospective design of the study.
: The authors declare that they have no competing interests.
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