Is there an exposure–effect relationship between body mass index and invasive mechanical ventilation, severity, and death in patients with COVID‐19? Evidence from an updated meta‐analysis. (22nd September 2020) - Liu, Menglu; Deng, Chao; Yuan, Ping; Ma, Jianyong; Yu, Peng; Chen, Jie; Zhao, Yujie; Liu, Xiao