Text and Data Mining valid from 2019-03-28
Received: 22 November 2018
Accepted: 20 February 2019
First Online: 28 March 2019
Ethics approval and consent to participate
: Ethical approval was obtained from the institutional review board of Seoul National University Hospital (Approval No. 1606-121-772). Oral consent was obtained from all participants before they took part in the study. Oral consent was approved by the ethics committee since this study did not collect any identifiable information from the study participants and potential risks to participant was minimal. Participants were informed that they could leave the study at any time without penalty, and all the responses were kept confidential.
: Not applicable
: The authors declare that they have no competing interests.
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