Funding for this research was provided by:
National Major Project (2018ZX10103001-004)
Received: 5 December 2019
Accepted: 3 July 2020
First Online: 31 July 2020
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Beijing Ditan Hospital, Capital Medical University. This study used data collected from patient records while maintaining patient anonymity. In view of no more than minimal risk of harm to patient subjects, a waiver of patient informed consent was approved by the institutional review board.
: Not applicable.
: The authors declare that they have no competing interests.