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Murphy CC, Craddock Lee SJ, Geiger AM, Cox JV, Ahn C, Nair R, Gerber DE, Halm EA, McCallister K, Skinner CS.Murphy CC, et al. Among authors: halm ea.BMC Med Res Methodol. 2020 May 19;20(1):123. doi: 10.1186/s12874-020-01014-x.BMC Med Res Methodol. 2020.PMID: 32429848Free PMC article.Clinical Trial.