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Moeller NC, Korsholm L, Kristensen PL, Andersen LB, Wedderkopp N, Froberg K.Moeller NC, et al. Among authors: andersen lb.BMC Med Res Methodol. 2008 Apr 11;8:19. doi: 10.1186/1471-2288-8-19.BMC Med Res Methodol. 2008.PMID: 18405353Free PMC article.