Received: 2 April 2021
Accepted: 30 September 2021
First Online: 14 October 2021
: This study protocol complied with the Declaration of Helsinki and was approved by the ethics committee of Dokkyo Medical University (Acceptance No. R-20-1J). All the study subjects received an explanation of the procedures and possible risks of this study and gave their informed consent to participate.
: Not applicable.
: The authors declare that they have no competing interest.