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Lin JS, Whitlock E, O'Connor E, Bauer V.Lin JS, et al.Ann Intern Med. 2008 Oct 7;149(7):497-508, W96-9. doi: 10.7326/0003-4819-149-7-200810070-00011.Ann Intern Med. 2008.PMID: 18838730Free article.Review.
Williams SB, O'Connor E, Eder M, Whitlock E.Williams SB, et al.Rockville (MD): Agency for Healthcare Research and Quality (US); 2009 Apr. Report No.: 09-05130-EF-1.Rockville (MD): Agency for Healthcare Research and Quality (US); 2009 Apr. Report No.: 09-05130-EF-1.PMID: 20722167Free Books & Documents.Review.