1. Department of Social Medicine and Health Management, Xiangya School of Public Health, Central South University, Changsha, China
2. College of Data Science and Information Engineering, Guizhou Minzu University, Guiyang, Guizhou Province, China
3. Department of Mathematics and Statistics, Mzuzu University, Malawi
4. Department of Epidemiology and Health Statistics, Xiangya School of Public Health, Central South University, Changsha, China
5. School of Medicine and Health Management, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China