1. Sagawa Akira Rheumatology Clinic,
Sapporo Excellent Building 5F, North-1, West-7, Chuo-ku 060-0001 Sapporo, Japan
2. Tomakomai City Hospital,
1-5-20 Shimizu-cho, Tomakomai 053-8567,, Japan
3. Ohnishi Clinic Internal Medicine and Rheumatology,
5-4-6 Atsubetsuchuo-2, Atsubetsu-ku, Sapporo 004-0052, Japan
4. Sapporo City General Hospital,
North-11, West-13-1-1, Chuo-ku, Sapporo 060-8604, Japan
5. Yamanotedori Yagi Hospital,
5-1-35 Nishino-3, Nishi-ku, Sapporo 063-0033, Japan
6. KKR Sapporo Medical Center,
6-3-40 Hiragishi-1, Toyohira-ku, Sapporo 062-0931, Japan
7. Hokkaido Medical Center for Rheumatic Diseases,
3-1-45 Kotoni-1, Nishi-ku, Sapporo 063-0811, Japan
8. Hokkaido Medical Center,
7-1-1 Yamanote-5, Nishi-ku, Sapporo 063-0005, Japan
9. Ohsaki Clinic,
9-6-21 Shinkotoni-7, Kita-ku, Sapporo 001-0907,, Japan