Funding for this research was provided by:
Japan Society for the Promotion of Science (JP18H04126)
Ministry of Health, Labour and Welfare (H30-Iryou-Ippan-013)
Received: 10 July 2020
Accepted: 29 December 2020
First Online: 28 January 2021
Ethics approval and consent to participate
: Ethics approval for this study was obtained from Nara Medical University. (Authorization number: 1123-4). The requirement for informed consent was waived because of the anonymized nature of the claims datasets. The datasets generated during the current study complied with the publication policy of Nara Prefecture.
: Not applicable.
: The authors declare that they have no competing interests.