1. Department of Neurology, Saitama Medical University, 38 Morohongo, Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan
2. Physical Education and Health Center, Nagaoka University of Technology, Niigata 940-2137, Japan
3. Department of Neurology, Saitama Neuropsychiatric Institute, Saitama 338-8577, Japan
4. Headache Center and Department of Neurology, Tominaga Hospital, Osaka 556-0017, Japan
5. Ohbayashi Clinic, Tochigi 321-0933, Japan
6. Department of Neurology, Japanese Red Cross Shizuoka Hospital, Shizuoka 420-0853, Japan
7. Sendai Headache and Neurology Clinic, Sendai 982-0014, Japan
8. Department of Neurology, Jichi Medical University Saitama Medical Center, Saitama 330-8503, Japan