1. Department of Nursing, West China Second University Hospital, Sichuan University/West China School of Nursing Sichuan University Chengdu China
2. Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University) Ministry of Education Chengdu China
3. Department of Health Policy and Management, West China School of Public Health/West China Fourth Hospital Sichuan University Chengdu China