Funding for this research was provided by:
Japanese Society of Intensive Care Medicine
Received: 8 April 2021
Accepted: 25 May 2021
First Online: 1 June 2021
: This study was approved by the Research Ethics Committee of the University of Tokyo (Approval number: 2020242NI-(1)). Consent to participate was waived because of the anonymous nature of the data.
: Not applicable.
: HE, NI, and HM are affiliated with the Department of Healthcare Quality Assessment at the University of Tokyo. The department is a social collaboration department supported by grants from the National Clinical Database, Johnson & Johnson K.K., and Nipro Corporation. The other authors do not have any competing interests to declare.