Received: 25 April 2020
Accepted: 23 December 2020
First Online: 13 January 2021
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Tohoku University Graduate School of Medicine (2017-856). At the time of conducting the survey, the method and intent of the survey were explained to participants. Further, all the participants provided written informed consent and were assured that the contents of the interviews would be recorded and that their statements would be reported anonymously.
: Not applicable.
: The authors declare that they have no competing interests.