Received: 4 April 2022
Accepted: 30 May 2022
First Online: 4 June 2022
: The study was approved by the ethics committees of Shiraiwa Medical Clinic (approval number, 2020902; approval date, September 2, 2020) and that of Osaka University Hospital (approval number 15395–3; approval date, September 7, 2020). Informed consent was exempted and instead relevant information regarding the study was open to the public, according to the Ethical Guidelines for Medical and Health Research Involving Human Subjects in Japan. The requirement for informed consent was waived by the Ethics Committee of Shiraiwa Medical Clinic and that of Osaka University Hospital, because of the retrospective nature of the study.
: Not applicable.
: The authors declare that they have no competing interests.