Chao Y.-S.HSING-CHIEN WUWu C.-J.Chen W.-C.2021-11-082021-11-0820181932-6203https://www.scopus.com/inward/record.uri?eid=2-s2.0-85050301981&doi=10.1371%2fjournal.pone.0197859&partnerID=40&md5=1caf37868863081cc75699bfd4ee49fehttps://scholars.lib.ntu.edu.tw/handle/123456789/586549Index or illusion: The case of frailty indices in the Health and Retirement Studyjournal article10.1371/journal.pone.0197859300209232-s2.0-85050301981