1. Department of PsychiatryNational Disaster Medical CenterTachikawaJapan
2. School of Distance Learning, Musashino UniversityNishi‐TokyoJapan
3. Clinical Research Institute, National Disaster Medical CenterTachikawaJapan
4. Division of Health Care ResearchCenter for Public Health Sciences, National Cancer CenterChuo‐ku, TokyoJapan