Funding for this research was provided by:
Japan Society for the Promotion of Science (17K19793, 18H04071, 20K20774)
Kitanihon Computer Service Co. Ltd. (N/A)
Received: 4 November 2020
Accepted: 10 May 2021
First Online: 16 June 2021
: The welfare offices of the municipalities agreed to provide anonymised data to the authors via a system company, which had provided management software for the public assistance database to the municipality welfare offices. The study protocol was approved by the Ethics Committee of the Graduate School of Medicine, University of Tokyo (Approval No: 11503).
: Not applicable.
: Daisuke Nishioka, Keiko Ueno, Shiho Kino, and Jun Aida declare no competing interests associated with this manuscript. Naoki Kondo conducted collaborative research with Kitanihon Computer Service Co. Ltd. (KITACOM) that provided the data used in the present study. Naoki Kondo received a research fund and a scholarship donation from KITACOM.