{{Cite journal| doi = 10.1016/j.cger.2023.05.004| issn = 1879-8853 (Electronic) 0749-0690 (Linking)| volume = 39| issue = 4| pages = 475–489| last1 = Nickel| first1 = C. H.| last2 = Kellett| first2 = J.| title = Assessing Physiologic Reserve and Frailty in the Older Emergency Department Patient: Should the Paradigm Change?| journal = Clin Geriatr Med| date = 2023-10-06| pmid = 37798060}}