Baek, Seung Don
Kang, Jae-Young
Yu, Hoon
Shin, Seulgi
Park, Hyang-Sook
Kim, Mi-Soon
Lee, Eun Kyoung
Kim, So Mi
Chang, Jai Won
Article History
Received: 9 January 2018
Accepted: 31 August 2018
First Online: 20 September 2018
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of the Asan Medical Center. Informed consent was not obtained because of the retrospective nature of the study.
: The authors declare that they have no competing interests.
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