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Article History

Received: 30 July 2018

Accepted: 15 April 2019

First Online: 27 April 2019

Ethics approval and consent to participate

: The study’s protocol was approved by the institutional review board of Boramae Medical Center (# 16–2013-34) and complied with the tenets of the 1964 Declaration of Helsinki and its later amendments. Written informed consent was obtained from all participants.

: Not applicable.

: The authors declare that they have no competing interests.

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