Received: 28 November 2019
Accepted: 6 August 2020
First Online: 24 August 2020
Ethics approval and consent to participate
: This study was conducted according to the Helsinki Declaration. The methods and procedures of this study were reviewed and approved by the Review Board of the Kao Corporation (Tokyo, Japan) (No. 072-170808) and registered to the University Hospital Medical Information Network Center Registry of Japan (registration No. UMIN000029666) before enrollment of participants. Informed consent from all subjects was obtained prior to participation.
: Not applicable
: The authors declare that they have no competing interests.