Shan, Xuzheng
Wang, Yongqin
Song, Ruihong
Wei, Wen
Liao, Hongxiu
Huang, Huang
Xu, Chunqiong
Chen, Lvlin
Li, Shiyun
Funding for this research was provided by:
Science and Technology Project of the Health Planning Committee of Sichuan (18PJ576)
Article History
Received: 25 June 2019
Accepted: 13 August 2020
First Online: 26 August 2020
Ethics approval and consent to participate
: All data were obtained from publicly available data sources, supplied and analysed in an anonymous format, without access to personal identifying information. Therefore, our study was exempt from institutional review board assessment. All authors declare that they approve this version of the manuscript.
: Not Applicable.
: The authors declare that they have no competing interests.