title: The authors reply.
authors.affiliation: Department of Intensive Care Medicine, Chi Mei Medical Center, Tainan, Taiwan, Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Intensive Care Medicine, Chi Mei Medical Center, Tainan, Taiwan.
authors.forename: Hsiu-Nien
authors.initials: HN
authors.lastname: Shen
authors.forename: Chin-Li
authors.initials: CL
authors.lastname: Lu
authors.forename: Hsi-Hsing
authors.initials: HH
authors.lastname: Yang