[1] Jichi Med Univ, Ctr Community Med, 3311-1 Yakushiji, Shimotsuke, Tochigi 3290498, Japan
[2] Jichi Med Univ, Dept Surg, 3311-1 Yakushiji, Shimotsuke, Tochigi 3290498, Japan
[3] Univ Tokyo, Tokyo Univ Hosp, Grad Sch Med, Dept Hlth Management & Policy,Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan
[4] Hiroshima Univ, Fac Med, Dept Community Based Med Syst, Minami Ku, 1-2-3 Kasumi, Hiroshima, Hiroshima 7348551, Japan
[5] Chiba Univ Hosp, Dept Med Community Network & Discharge, Chuo Ku, 1-8-1 Inohana, Chiba, Chiba 2608677, Japan
[6] Tokyo Univ Hosp, Dept Planning Informat & Management, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan
[7] Univ Tokyo, Sch Publ Hlth, Dept Clin Epidemiol & Hlth Econ, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan