Text and Data Mining valid from 2019-11-05
Received: 4 July 2019
Accepted: 15 October 2019
First Online: 5 November 2019
Ethics approval and consent to participate
: This retrospective study was approved by the ethics committee of Tongji Hospital of Tongji Medical College of Huazhong University of Science and Technology. Due to the retrospective nature of this study, written informed consent was not required. This retrospective study was conducted in accordance with The Declaration of Helsinki Principles.
: Not applicable.
: The authors declare that they have no competing interests.