1. Department of Occupational and Community Health Nursing, School of Health Sciences, University of Occupational and Environmental Health, Japan, Kitakyushu 807-8555, Japan
2. Department of Radiation Regulatory Science Research, National Institute of Radiological Sciences, National Institute for Quantum Science and Technology, Chiba 263-8555, Japan
3. Department of Radiology, Hospital of the University of Occupational and Environmental Health, Japan, Kitakyushu 807-8556, Japan
4. Department of Radiology, Shinkomonji Hospital, Kitakyushu 800-0057, Japan
5. Department of Radiological Technology, Kawasaki Medical School Hospital, Kurashiki 701-0192, Japan
6. Occupational Health Training Center, University of Occupational and Environmental Health, Japan, Kitakyushu 807-8555, Japan