Funding for this research was provided by:
Capital General Medical Research Special Project (15QK12)
Article History
Received: 27 August 2020
Accepted: 22 March 2021
First Online: 1 April 2021
Declarations
:
: The study protocol was approved by the Institutional Review Board for Human Studies of Beijing Chaoyang Hospital, Beijing, China. The review board exempted the acquisition of informed consent because this was a retrospective study. Patients’ data confidentiality was fully respected during data collection and the preparation of the manuscript.
: Not applicable – this study does not contain any patient personal details.
: The authors declare they have no competing interests.