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Guyatt G, Vist G, Falck-Ytter Y, Kunz R, Magrini N, Schunemann H.Guyatt G, et al.Evid Based Med. 2006 Feb;11(1):2-4. doi: 10.1136/ebm.11.1.2-a.Evid Based Med. 2006.PMID: 17216711No abstract available.