Funding for this research was provided by:
China Medical Board (15-217,2016-2018)
National Natural Science Foundation of China (71773002)
Text and Data Mining valid from 2020-03-18
Received: 26 July 2019
Accepted: 26 February 2020
First Online: 18 March 2020
Ethics approval and consent to participate
: No administrative permissions were required to access and use the mediation records described in our study.
: Not applicable.
: The authors declare that they have no competing interests.