1. Department of Nursing, College of Medicine, National Taiwan University, Taipei, Taiwan2Department of Nursing, National Taiwan University Hospital, Taipei, Taiwan
2. Department of Nursing, College of Medicine, National Taiwan University, Taipei, Taiwan3Department of Nursing, Sijhih Cathy General Hospital, New Taipei City, Taiwan
3. Department of Surgery, College of Medicine, National Taiwan University, Taipei, Taiwan5Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
4. Institute of Statistics, National Chiao Tung University, Hsinchu, Taiwan
5. Taiwan Center for Disease Control, Taipei, Taiwan
6. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts9Institute for Aging Research, Hebrew Senior-Life, Boston, Massachusetts