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Gagnier JJ, Morgenstern H, Altman DG, Berlin J, Chang S, McCulloch P, Sun X, Moher D; Ann Arbor Clinical Heterogeneity Consensus Group.Gagnier JJ, et al.BMC Med Res Methodol. 2013 Aug 30;13:106. doi: 10.1186/1471-2288-13-106.BMC Med Res Methodol. 2013.PMID: 24004523Free PMC article.