Yu-Sheng Lin1,2, Pi-Hua Liu2,3, Ning-Hung Chen4. 1. Healthcare Center, Chang Gung Memorial Hospital and Chang Gung University, Taipei, Taiwan. 2. Department of Internal Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan. 3. Clinical Informatics and Medical Statistics Research Center, College of Medicine, Chang Gung University, Taoyuan, Taiwan. 4. Sleep Center, Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, No.123, Dinghu RD., Guishan, Township, Taoyuan County, Taiwan. nhchen@adm.cgmh.org.tw.