1. Department of Public Health; Kitasato University School of Medicine; 1-15-1 Kitasato, Minami-ku Sagamihara Kanagawa 252-0374 Japan
2. National Center for Global Health and Medicine; 1-21-1 Toyama Shinjuku-ku Tokyo 162-8655 Japan
3. Department of Health and Physical Education; Fukuoka University of Education; 1-1 Akamabunkyo-machi, Munakata Fukuoka 811-4192 Japan
4. School of Health Sciences, Faculty of Health and Medicine; University of Newcastle; Ourimbah 2258 Australia