[1] Natl Healthcare Grp, Singapore, Singapore
[2] Khoo Teck Puat Hosp, Alexandra Hlth Syst, 90 Yishun Cent, Singapore 768828, Singapore
[3] Duke NUS Med Sch, Singapore, Singapore
[4] Univ Pittsburgh, Pittsburgh, PA USA
[5] Natl Univ Singapore, Lee Kuan Yew Sch Publ Policy, Singapore, Singapore
[6] Geriatr Educ & Res Inst, Singapore, Singapore