Received: 10 May 2021
Accepted: 17 June 2021
First Online: 3 July 2021
: The study protocol was approved by the Ethics Committee of Keio University School of Medicine (IRB Approval Number: 20180224). Written informed consent from the participants was waved, but the opportunity to opt out of the study was provided to the participants.
: Not applicable
: The authors declare that they have no competing interests.