Text and Data Mining valid from 2019-03-04
Received: 11 September 2018
Accepted: 20 February 2019
First Online: 4 March 2019
Ethics approval and consent to participate
: This study was approved by the Institutional of Review Board at Gyeongsang National University (GIRB-G13-X-0021). Written informed consent was obtained from the participants who agreed to participate in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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