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Grooten L, Vrijhoef HJM, Calciolari S, Ortiz LGG, Janečková M, Minkman MMN, Devroey D.Grooten L, et al. Among authors: calciolari s.BMC Med Res Methodol. 2019 Mar 18;19(1):63. doi: 10.1186/s12874-019-0704-1.BMC Med Res Methodol. 2019.PMID: 30885141Free PMC article.