[1] Beijing Childrens Hosp, Ctr Clin Epidemiol & Evidence Based Med, Natl Ctr Childrens Hlth, Beijing, Peoples R China
[2] Natl Inst Hosp Adm, Hlth Qual Management Dept, Beijing, Peoples R China
[3] Capital Med Univ, Dept Publ Hlth, Beijing, Peoples R China