Xu, Min
Chen, Hui
Li, Hong-Wei
Article History
Received: 16 May 2021
Accepted: 30 March 2022
First Online: 7 April 2022
Declarations
:
: This was a retrospective study, and written informed consent was obtained from each participant on admission. This study was approved by the Institutional Review Board of Beijing Friendship Hospital. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institution and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
: Not applicable.
: The authors declare that they have no competing interests.