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Laiou E, Clutton-Brock TH, Lilford RJ, Taylor CA.Laiou E, et al.BMC Med Educ. 2011 Aug 11;11:57. doi: 10.1186/1472-6920-11-57.BMC Med Educ. 2011.PMID: 21834978Free PMC article.Clinical Trial.