Zhang Junguo, Qu Hongying, Li Cheng, Li Ziyi, Li Guanming, Tian Junzhang, Li Guowei
Center for Clinical Epidemiology and Methodology (CCEM), Guangdong Second Provincial General Hospital, Guangzhou, China.
Department of Pulmonary and Critical Care Medicine, Guangdong Second Provincial General Hospital, Guangzhou, China.
Front Public Health. 2020 Nov 2;8:562418. doi: 10.3389/fpubh.2020.562418. eCollection 2020.