[1] Shandong Univ, Cheeloo Coll Med, Ctr Hlth Management & Policy Res, Sch Publ Hlth, 44 Wenhuaxi Rd, Jinan 250012, Shandong, Peoples R China
[2] Shandong Univ, NHC Key Lab Hlth Econ & Policy Res, Jinan 250012, Peoples R China
[3] Univ Virginia, Coll Arts & Sci, Charlottesville, VA USA
[4] Univ Massachusetts, Dept Gerontol, Boston, MA 02125 USA
[5] Univ Virginia, Sch Med, Charlottesville, VA 22908 USA
[6] Home Ctr Care Inst, Chicago, IL 60173 USA