Text and Data Mining valid from 2019-06-13
Received: 4 March 2019
Accepted: 4 June 2019
First Online: 13 June 2019
Ethics approval and consent to participate
: This study was performed according to the Helsinki Declaration, and the Institutional Review Board of the Catholic University of Korea, College of Medicine approved the study protocol (approval number: SC17RES10080).
: Participation in this survey includes a statement of intent to publish.
: The author declares that he has no competing interests.