1. Graduate School of Comprehensive Human Sciences University of Tsukuba Tsukuba Ibaraki Japan
2. Emergency Department National Center for Maternal and Child Health Ulaanbaatar Mongolia
3. UB Songdo Hospital Ulaanbaatar Mongolia
4. Department of Statistics and Surveillance National Trauma and Orthopedic Research Center Ulaanbaatar Mongolia
5. Department of Epidemiology and Biostatistics Mongolian National University of Medical Sciences Ulaanbaatar Mongolia
6. Department of Global Public Health, Institute of Medicine University of Tsukuba Tsukuba Ibaraki Japan