Funding for this research was provided by:
Ministry of Health & Welfare, Republic of Korea (HI16C0047)
Received: 24 August 2018
Accepted: 20 December 2018
First Online: 7 February 2019
Ethics approval and consent to participate
: Written informed consent was obtained from each patient before participation in this study. This study was approved by the Institutional Review Board of The Catholic University of Korea.
: Not applicable.
: The authors declare that they have no competing interests.
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