1. Department of Public Health Sciences, Hokkaido University Graduate School of Medicine, Sapporo, Japan
2. Department of Health and Welfare Science, Asahikawa University, Asahikawa, Hokkaido, Japan
3. Department of Health Science, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
4. Department of Medical Management and Informatics, Hokkaido Information University, Ebetsu, Hokkaido, Japan
5. Department of Comprehensive Development Nursing, Faculty of Health Sciences, Hokkaido University, Sapporo, Japan
6. Center for Environmental and Health Sciences, Hokkaido University, Sapporo, Japan