Funding for this research was provided by:
Text and Data Mining valid from 2018-12-01
Received: 25 August 2017
Accepted: 21 November 2018
First Online: 18 December 2018
Ethics approval and consent to participate
: The study was approved by the Wonkwang University of Institutional Review Board (WKIRB-201511-BM-002). Written informed consent in the study was given by all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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