Funding for this research was provided by:
Korea Health Industry Development Institute (HI16C1186)
Text and Data Mining valid from 2018-12-01
Received: 8 May 2018
Accepted: 19 November 2018
First Online: 4 December 2018
Ethics approval and consent to participate
: The present study was reviewed and approved by the Institutional Review Board of Korea University (1040548-KU-IRB-16-203-A-1). This was a registry-based study without personal contact and consent to participate was not required.
: Not applicable.
: The authors declare that they have no competing interests.
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