title: Lower and Better.
authors.affiliation: Emergency Department, Peking Union Medical College Hospital, Peking, China.
authors.forename: Xuezhong
authors.initials: X
authors.lastname: Yu
authors.affiliation: Emergency Department, Peking Union Medical College Hospital, Peking, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Emergency Department, Peking Union Medical College Hospital, Peking, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.affiliation: Emergency Department, Peking Union Medical College Hospital, Peking, China.
authors.forename: Dingyu
authors.initials: D
authors.lastname: Tan