[1] Univ Tokyo, Grad Sch Med, Dept Geriatr Med, Tokyo 1138655, Japan
[2] Kyorin Univ, Sch Med, Dept Geriatr Med, Mitaka, Tokyo 181, Japan
[3] Nagoya Univ, Grad Sch Med, Dept Geriatr Med, Nagoya, Aichi 4648601, Japan
[4] Kyoto Univ, Grad Sch Med, Dept Human Hlth Sci, Kyoto, Japan
[5] Tohoku Univ, Grad Sch Med, Dept Geriatr Med, Sendai, Miyagi 980, Japan
[6] Tokyo Metropolitan Geriatr Hosp, Tokyo 173, Japan
[7] Inst Gerontol, Tokyo, Japan
[8] Natl Ctr Geriatr & Gerontol, Obu, Japan
[9] Teikyo Univ, Sch Med, Dept Urol, Tokyo 173, Japan
[10] Japan Assoc Geriatr Hlth Serv Facil, Tokyo, Japan
[11] Japan Assoc Med & Care Facil, Tokyo, Japan
[12] Japan Med Assoc, Tokyo, Japan
[13] Univ Tokyo, Grad Sch Humanities & Sociol, Tokyo 1138655, Japan
[14] Gakushuin Univ, Fac Law, Tokyo 171, Japan
[15] Univ Tokyo, Inst Gerontol, Tokyo 1138655, Japan