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Hamza TH, Arends LR, van Houwelingen HC, Stijnen T.Hamza TH, et al. Among authors: stijnen t.BMC Med Res Methodol. 2009 Nov 10;9:73. doi: 10.1186/1471-2288-9-73.BMC Med Res Methodol. 2009.PMID: 19903336Free PMC article.