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van Hoeven LR, Janssen MP, Roes KC, Koffijberg H.van Hoeven LR, et al. Among authors: janssen mp.BMC Med Res Methodol. 2015 Oct 23;15:90. doi: 10.1186/s12874-015-0089-8.BMC Med Res Methodol. 2015.PMID: 26497748Free PMC article.