Park, Vivian Youngjean
Kim, Eun-Kyung
Kim, Min Jung
Moon, Hee Jung
Yoon, Jung Hyun http://orcid.org/0000-0002-2100-3513
Article History
Received: 12 September 2017
Accepted: 16 January 2018
First Online: 22 January 2018
Ethics approval and consent to participate
: The study protocol was approved by the Severance Hospital Institutional Review Board (approval number 4–2016-1063). As data were analyzed anonymously, the requirement for informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.
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