Funding for this research was provided by:
the National Natural Science Foundation of China (82070699)
Discipline Promotion Project of Xijing Hospital (XJZT18ML16)
Received: 28 July 2020
Accepted: 20 December 2020
First Online: 6 January 2021
Ethics approval and consent to participate
: This retrospective study was approved by the ethics committee of Xijing Hospital, the Fourth Military Medical University, China, and performed in accordance with the Declaration of Helsinki. Because of the retrospective design of the study, the need to obtain informed consent from eligible patients was waived by the ethics committee.
: Not applicable.
: The authors declare that they have no competing interests.