Li, Man
Wang, Zhuo-qun
Zhang, Lu
Zheng, Hao
Zhou, Mai-geng
Liu, Dian-wu
Funding for this research was provided by:
Project of Hebei Provincial Health Planning Commission (20180699)
Article History
Received: 18 July 2019
Accepted: 11 September 2020
First Online: 29 September 2020
Ethics approval and consent to participate
: Not applicable.
: Not applicable.
: The authors declare that they have no competing interests.