Yang, Yin
Deng, Hui
Yang, Qingqing
Ding, Xianbin
Mao, Deqiang
Ma, Xiaosong
Xiao, Bangzhong
Zhong, Zhaohui http://orcid.org/0000-0002-8057-3065
Funding for this research was provided by:
Chongqing Municipal Health Bureau (0611-BZ1800401421AF (18C1835))
Article History
Received: 3 July 2020
Accepted: 24 August 2020
First Online: 10 September 2020
Ethics approval and consent to participate
: The study was approved by the Chongqing Medical University Committee. And considering the educational level of the elderly (many old people cannot write), we only obtained the oral informed consent of the elderly.
: Not applicable.
: The authors declare that there is no conflict of interests.