Funding for this research was provided by:
Ministry of Health and Welfare (HM15C1072, HL19C0018)
Text and Data Mining valid from 2019-04-11
Received: 7 January 2019
Accepted: 29 March 2019
First Online: 11 April 2019
Ethics approval and consent to participate
: Written informed consent was obtained from all participants before conducting self-questionnaires and face-to-face interviews. This study was conducted with the approval of institutional review board, the Samsung Seoul Hospital Clinical Research Committee. (IRB No.2016-05-014)
: Not applicable.
: The authors declare that they have no competing interests.
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