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Forbes LJ, Nicholls CM, Linsell L, Graham J, Tompkins C, Ramirez AJ.Forbes LJ, et al. Among authors: ramirez aj.BMC Med Res Methodol. 2010 Dec 22;10:110. doi: 10.1186/1471-2288-10-110.BMC Med Res Methodol. 2010.PMID: 21176229Free PMC article.