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Gerhard T, Delaney JA, Cooper-Dehoff RM, Shuster J, Brumback BA, Johnson JA, Pepine CJ, Winterstein AG.Gerhard T, et al.BMC Med Res Methodol. 2012 Aug 6;12:119. doi: 10.1186/1471-2288-12-119.BMC Med Res Methodol. 2012.PMID: 22866767Free PMC article.Clinical Trial.