Funding for this research was provided by:
National Basic Research Program of China (973 Program) (No. 2016YFC0901501)
National Natural Science Fund (No. 81472870)
CAMS Innovation Fund for Medical Sciences (No. 2016-I2M-1-002)
Text and Data Mining valid from 2019-08-08
Received: 4 March 2019
Accepted: 18 July 2019
First Online: 8 August 2019
Ethics approval and consent to participate
: The study protocol was approved by the Research and Ethics Board of the PUMCH. Informed consent was obtained from all patients before the study questionnaires were completed.
: All authors have given consent for publication.
: The authors have no conflicts of interest to disclose.