Funding for this research was provided by:
National Natural Science Foundation of China (71804049)
National Social Science Foundation of China (18ZDA085)
Text and Data Mining valid from 2019-12-01
Received: 26 May 2019
Accepted: 4 October 2019
First Online: 2 December 2019
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of the Tongji Medical College Institutional Review Board, Huazhong University of Science and Technology, Wuhan, China. Informed consent was obtained from all survey participants.
: Not applicable.
: The authors declare that they have no competing interests.