Text and Data Mining valid from 2019-12-01
Received: 28 November 2018
Accepted: 3 December 2019
First Online: 12 December 2019
Ethics approval and consent to participate
: Ethical clearance was obtained from the respective institutional research ethics committees of Tokyo Bay Urayasu Ichikawa Medical Centre, Chiba University Hospital, Tsukuba University Hospital, and Kyorin University Hospital. The need for approval was waived by the institutional research ethics committee of St. Marianna University Hospital. Participation was voluntary, and all participants provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.