Funding for this research was provided by:
Natural Science Foundation of Zhejiang Province (LQ18H180002)
National Natural Science Foundation of China (31700690)
Text and Data Mining valid from 2019-11-29
Received: 22 March 2019
Accepted: 18 November 2019
First Online: 29 November 2019
Ethics approval and consent to participate
: The survey was approved by the Medical Ethics Committee of the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China (No.2017–58). Because the data were recorded retrospectively and without any specific intervention, the Medical Ethics Committee waived informed consent from the subjected patients. Data were deidentified to protect the privacy and maintain confidentiality of patient information. It was conducted in accordance with the Declaration of Helsinki.
: For this type of study formal consent is not required.
: The authors declare that they have no competing interests.