Kajihara, Toshiki
Yahara, Koji
Hirabayashi, Aki
Kurosu, Hitomi
Sugai, Motoyuki
Shibayama, Keigo
Article History
Received: 29 January 2021
Accepted: 5 April 2021
First Online: 17 April 2021
Declarations
:
: Patient identifiers were de-identified by each hospital before data submission to JANIS. The anonymous data stored in the JANIS database were exported and analyzed.The protocol of this study was approved by the Ministry of Health, Labor and Welfare (approval number 0417–1) according to Article 32 of the Statistics Act and in accordance with the Helsinki Declaration. The requirement for informed consent was waived by the Ministry of Health, Labor and Welfare (approval number 0417–1).
: Not applicable.
: The authors declare that they have no competing interests.