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Helfand M, Buckley DI, Freeman M, Fu R, Rogers K, Fleming C, Humphrey LL.Helfand M, et al. Among authors: buckley di.Ann Intern Med. 2009 Oct 6;151(7):496-507. doi: 10.7326/0003-4819-151-7-200910060-00010.Ann Intern Med. 2009.PMID: 19805772Free article.Review.