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Finkelman MD, Kulich RJ, Zoukhri D, Smits N, Butler SF.Finkelman MD, et al. Among authors: kulich rj.BMC Med Res Methodol. 2013 Oct 20;13:126. doi: 10.1186/1471-2288-13-126.BMC Med Res Methodol. 2013.PMID: 24138225Free PMC article.