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Badgett RG, Paukert JL, Levy LS.Badgett RG, et al.BMC Med Educ. 2001;1:3. doi: 10.1186/1472-6920-1-3. Epub 2001 Aug 7.BMC Med Educ. 2001.PMID: 11532204Free PMC article.Clinical Trial.