Funding for this research was provided by:
Ministry of Health & Welfare, Republic of Korea (HC14C1062)
Text and Data Mining valid from 2018-05-15
Received: 24 November 2017
Accepted: 2 May 2018
First Online: 15 May 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the Catholic University of Korea (approval number: HC17RESI0044). This study was retrospective clinical study using medical record, written informed consent was waivered by the ethics committee.
: The authors declare that they have no competing interests.
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