[1] Yonsei Univ, Grad Sch Publ Hlth, Dept Healthcare Management, Seoul, South Korea
[2] Harvard Med Sch, Hinda & Arthur Marcus Inst Aging Res, Hebrew SeniorLife, Boston, MA USA
[3] Yonsei Univ, Inst Hlth Serv Res, Seoul, South Korea
[4] Dankook Univ, Dept Hlth Adm, Cheonan, South Korea
[5] Yonsei Univ, Coll Med, Dept Prevent Med, Seoul, South Korea
[6] Ajou Univ, Sch Med, Dept Radiat Oncol, Suwon, South Korea