Funding for this research was provided by:
Chongqing Science and Technology Commission of the People’s Republic of China in 2017 (cstc2017jcyjAX0185)
Chongqing Education Committee “Humanities and Social Sciences Research Projects” (14SKD09)
Text and Data Mining valid from 2020-01-18
Received: 1 August 2019
Accepted: 2 January 2020
First Online: 18 January 2020
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Chongqing Medical University and was conducted in accordance with the Declaration of Helsinki (record number: 2017016).
: Not applicable.
: The authors declare that they have no competing interests.