1. Department of Burns, Beijing Jishuitan Hospital, Xicheng District, Beijing City, Peopleʼs Republic of China
2. Peking University Fourth School of Clinical Medicine, Xicheng District, Beijing City, Peopleʼs Republic of China
3. Department of Statistics, Iowa State University, Ames, Iowa, USA
4. Clinical Epidemiology Research Center, Xicheng District, Beijing Jishuitan Hospital, Beijing City, Peopleʼs Republic of China