Article History
Received: 10 April 2021
Revised: 13 June 2021
Accepted: 14 June 2021
First Online: 23 June 2021
Declarations
:
: The authors declare that they have no conflicts of interest.
: Approved by Gunma University Ethical Review Board for Medical Research Involving Human Subjects. HS2020-079, 2020/07/17, retrospectively registered.
: Due to the retrospective nature of the study, informed consent was carried out using the opt-out method on our hospital website.