1. Department of Respiratory Medicine; Faculty of Medicine and Graduate School of Medicine; Hokkaido University; Sapporo Japan
2. Otolaryngology Head and Neck Surgery; Hokkaido University School of Medicine; Sapporo Japan
3. Shino-Test Corporation; Kanagawa Japan
4. Division of Medical Biochemistry; Department of Biomolecular Sciences; Saga Medical School; Saga Japan
5. Department of Biostatistics; Faculty of Medicine and Graduate School of Medicine; Hokkaido University; Sapporo Japan
6. University of Pittsburgh Asthma Institute at UPMC/University of Pittsburgh School of Medicine; Pittsburgh PA USA