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Butler M, Nelson VA, Davila H, Ratner E, Fink HA, Hemmy LS, McCarten JR, Barclay TR, Brasure M, Kane RL.Butler M, et al. Among authors: barclay tr.Ann Intern Med. 2018 Jan 2;168(1):52-62. doi: 10.7326/M17-1530. Epub 2017 Dec 19.Ann Intern Med. 2018.PMID: 29255909Free article.