1. Chinese Evidence-based Medicine Center, West China Hospital; Sichuan University; Chengdu China
2. Chengdu University of Traditional Chinese Medicine; Chengdu China
3. School of Public Administration; Southwest Jiaotong University; Chengdu China
4. West China Women's and children's Hospital; Sichuan University; Chengdu China
5. West China Medical School, West China Hospital; Sichuan University; Chengdu China