[1] Sichuan Univ, West China Hosp, Inst Integrated Tradit Chinese & Western Med, Div Internal Med, Chengdu 610041, Peoples R China
[2] Sichuan Univ, West China Hosp, Dept Med Adm, Chengdu, Peoples R China
[3] Sichuan Univ, West China Hosp, Dept Evidence Based Med & Clin Epidemiol, Chengdu, Sichuan, Peoples R China
[4] Sichuan Univ, West China Hosp, Canc Ctr, Div Head & Neck Tumor Multimodal Treatment, Chengdu, Peoples R China
[5] Sichuan Univ, West China Hosp, Int Med Ctr, Gen Practice Unit, Chengdu 610041, Peoples R China
[6] Sichuan Univ, West China Hosp, Dept Period Press, Chengdu 610041, Peoples R China