,
Ko, Byuk Sung
Kim, Kyuseok
Choi, Sung-Hyuk
Kang, Gu Hyun
Shin, Tae Gun
Jo, You Hwan
Ryoo, Seung Mok
Beom, Jin Ho
Kwon, Woon Yong
Han, Kap Su
Choi, Han Sung
Chung, Sung Phil
Suh, Gil Joon
Lim, Tae Ho
Kim, Won Young
Article History
Received: 19 July 2017
Accepted: 27 December 2017
First Online: 24 February 2018
Ethics approval and consent to participate
: The institutional review board of each institution approved the study protocol and informed consent was obtained before data collection.
: Not applicable.
: The authors declare that they have no competing interests.
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