Funding for this research was provided by:
the National Science and Technology Major Project of China (2018ZX10715004)
Received: 20 July 2020
Accepted: 6 April 2021
First Online: 12 April 2021
: The study was approved by the ethics committee of the School of Public Health, Sun Yat-sen University (Reference No.: 2020-012). Informed consents were obtained online before self-administering the questionnaire by clicking a survey link after being briefed about the background, aims, anonymous nature and length (about 8–12 min to complete) of the survey.
: Not applicable.
: The authors declare that they have no competing interests.