Received: 7 December 2020
Accepted: 22 December 2021
First Online: 3 January 2022
: This study was conducted to the ethical guideline of the Declaration of Helsinki and was centrally approved by the Institutional review board of Saga Medical Center Koseikan (study ID 17-09-01-02), and also approved by the Institutional review boards or ethics committee of following institutions: Imari Arita Kyoritsu Hospital, Japanese Red Cross Kumamoto Hospital, Kagoshima City Hospital, Oita University Hospital, Kagoshima University Hospital, Kurume University Hospital, Japan Community Healthcare Organization Kyushu Hospital, Saiseikai Sendai Hospital, Nagasaki University Hospital, Hamanomachi Hospital, Sasebo Kyosai Hospital, Karatsu Red Cross Hospital and Fukuoka Wajiro Hospital. Because this study was a retrospective observational study carried out in Japan, informed consent was obtained using the opt-in/opt-out approach according to each participating institution’s policy.
: Not applicable
: M.S. received a personal fee from Sysmex Corporation; S.A. received personal fees from Taiho Pharmaceutical, Novartis Pharma, Chugai, Bristol–Myers Squibb, Daiichi–Sankyo, and AstraZeneca; A.M. received fees from Eli Lilly, Chugai and Takeda; T.S. received fees from Taiho Pharmaceutical, Chugai and Takeda; T.O. received a fee from Chugai. The other authors have no competing interests or financial disclosures to declare.