Funding for this research was provided by:
Japan Society for the Promotion of Science (JP15K15167, JP17K19812)
Japan Science and Technology Corporation (JP), RISTEX (JPMJRX18B3)
Osaka University International Joint Research Promotion Program
Ministry of Health, Labour and Welfare (H29‐Nanchitou(Nan)‐Ippan‐030 and 20FC1036, H29-Nanchitou(Nan)-Ippan 029 and 20FC1052)
Japan Foundation for Promoting Welfare of Small and Medium-sized Enterprises
National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC).
Received: 26 June 2020
Accepted: 15 January 2021
First Online: 1 February 2021
Ethics approval and consent to participate
: This study has been approved by the ethical review board of Osaka University Hospital (16234–6), and the ethical committee for epidemiology of Hiroshima University (E-1341-1). Participant consent was obtained through the registration process. Consent of members of the Steering Committee was obtained orally or by email after they had received an explanation about their expected roles.
: Not applicable.
: The authors declare that they have no competing interests.