1. Department of Gastroenterology, Xi’an People’s Hospital, Guangren Hospital Affiliated to Medical College of Xi’an Jiaotong University, Xi’an, China
2. Third Department of Medical Oncology, Shaanxi Provincial Cancer Hospital Affiliated to Medical College of Xi’an Jiaotong University, Xi’an, China
3. School of Continuing Education, Xi’an Jiaotong University, Xi’an, Shaanxi, China
4. School of public health, Capital Medical University, Beijing, China
5. The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, China
6. Department of Oncology, Xi’an Gaoxin Hospital, Xi’an, China