Received: 19 October 2020
Accepted: 7 December 2020
First Online: 10 January 2021
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board for Clinical Research of the Kochi Medical School (ERB-103996, 30–44) and performed in accordance with the Declaration of Helsinki. An opt-out system was in place for participant consent.
: Not applicable.
: The authors declare that they have no competing interests.