Funding for this research was provided by:
key Research and Development Program of Gansu Province (20YF3FA028)
Health Research Management Project of Gansu Province (GSWSKY-2019-79)
Article History
Received: 17 December 2020
Accepted: 11 February 2021
First Online: 19 February 2021
Ethics approval and consent to participate
: Not applicable.
: Not applicable.
: The authors declare no conflict of interest.