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Broeze KA, Opmeer BC, Bachmann LM, Broekmans FJ, Bossuyt PM, Coppus SF, Johnson NP, Khan KS, ter Riet G, van der Veen F, van Wely M, Mol BW.Broeze KA, et al. Among authors: opmeer bc.BMC Med Res Methodol. 2009 Mar 27;9:22. doi: 10.1186/1471-2288-9-22.BMC Med Res Methodol. 2009.PMID: 19327146Free PMC article.