title: Response.
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea.
authors.forename: Tae Jun
authors.initials: TJ
authors.lastname: Song
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea.
authors.forename: Sang Soo
authors.initials: SS
authors.lastname: Lee