Wang, Yong-xue
Deng, Shan
Article History
Received: 11 May 2020
Accepted: 12 August 2020
First Online: 24 August 2020
Ethics approval and consent to participate
: This study conformed to the guidelines explained in the Declaration of Helsinki and was approved by the ethics committee of Peking Union Medical College Hospital (PUMCH, Beijing, China). A waiver for the requirement of informed consent from the patients whose records were analysed was granted by the Chair of the Committee on the grounds of being a minimal risk study.
: Not applicable.
: The authors declare that they have no competing interests.