Text and Data Mining valid from 2019-03-29
Received: 9 May 2018
Accepted: 13 March 2019
First Online: 29 March 2019
Ethics approval and consent to participate
: The study was conducted according to the Declaration of Helsinki. The research protocol was approved by the Institutional Review Board (IRB) of Chonbuk National University Hospital. All participants gave written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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