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Gordijn M, Cremers EM, Kaspers GJ, Gemke RJ.Gordijn M, et al.Qual Life Res. 2011 Sep;20(7):1103-8. doi: 10.1007/s11136-010-9836-9. Epub 2011 Jan 19.Qual Life Res. 2011.PMID: 21246290Free PMC article.