1. Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei 114201, Taiwan, R.O.C
2. Department of Orthopedics, Taoyuan General Hospital, Ministry of Health and Welfare, Taoyuan 330, Taiwan, R.O.C
3. School of Public Health, National Defense Medical Center, Taipei 114201, Taiwan, R.O.C
4. Graduate Institute of Aerospace and Undersea Medicine, National Defense Medical Center, Taipei 114201, Taiwan, R.O.C
5. Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114201, Taiwan, R.O.C
6. Division of General Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 114202, Taiwan
7. Department of Surgery, Chiayi Branch, Taichung Veterans General Hospital, Chiayi City 60090, Taiwan