Text and Data Mining valid from 2020-05-05
Received: 3 October 2019
Accepted: 19 February 2020
First Online: 5 May 2020
Ethics approval and consent to participate
: Participants gave written consent for their responses to be used for research. This research was approved by the governing ethical body (Hangjeongshil) of the OCU, which checks and approves all research done at the OCU.
: The authors declare that they have no competing interests.