Funding for this research was provided by:
National Natural Science Foundation of China (71673187)
Shanghai Shenkang development research project (SHDC12019651)
Shanghai Three-year Action Plan for Public Health under Grant (GWV-10.1-XK15, GWV-10.1-XK18, GWV-10.2-XD13)
Strategic collaborative innovation team (SSMU-ZLCX20180601)
Received: 7 September 2020
Accepted: 6 January 2021
First Online: 15 January 2021
Ethics approval and consent to participate
: The study was also approved by the Ethics Committee of the School of Public Health, Shanghai Jiao Tong University.The study was approved by the Shanghai Jiao Tong University School of Medicine Public Health and Nursing Ethics Committee. Informed consent was signed by all participants before interviews. All participants were free to ask any questions and to withdraw if they did not wish to continue.
: Not applicable.
: The authors declare they have no competing interests.