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Pearce A, Law C, Elliman D, Cole TJ, Bedford H; Millennium Cohort Study Child Health Group.Pearce A, et al.BMJ. 2008 Apr 5;336(7647):754-7. doi: 10.1136/bmj.39489.590671.25. Epub 2008 Feb 28.BMJ. 2008.PMID: 18309964Free PMC article.