Received: 27 September 2020
Accepted: 8 December 2021
First Online: 20 December 2021
: This study was approved by Peking University (Ethical approval number: IRB00001052-18055). Informed consent was obtained online. When first opening the research link, the content related to informed consent was shown, and the employees were able to choose whether to complete the questionnaire or quit.We consider that they agreed to participate if they submitted the questionnaire through the link. The committee of Peking University approved this research design.
: Not applicable.
: We declare no competing interests.