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Brown CA, Cheng EM, Hays RD, Vassar SD, Vickrey BG.Brown CA, et al. Among authors: vickrey bg.Qual Life Res. 2009 Nov;18(9):1219-37. doi: 10.1007/s11136-009-9530-y. Epub 2009 Aug 28.Qual Life Res. 2009.PMID: 19714487Free PMC article.