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Alley DE, Crimmins E, Bandeen-Roche K, Guralnik J, Ferrucci L.Alley DE, et al.J Am Geriatr Soc. 2007 Nov;55(11):1801-7. doi: 10.1111/j.1532-5415.2007.01390.x. Epub 2007 Aug 28.J Am Geriatr Soc. 2007.PMID: 17727645Free PMC article.