1. Department of Epidemiology and Biostatistics, School of Public Health, Xinjiang Medical University, Urumqi, Xinjiang Uygur Autonomous Region, China
2. Department of Immunization Programme, Xinjiang Uygur Autonomous Region Center for Disease Control and Prevention, Urumqi, Xinjiang Uygur Autonomous Region, China
3. Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States of America
4. Cancer Prevention and Control Program, University of South Carolina, Columbia, SC, United States of America