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Kerber RA, O'Brien E, Smith KR, Cawthon RM.Kerber RA, et al. Among authors: cawthon rm.J Gerontol A Biol Sci Med Sci. 2001 Mar;56(3):B130-9. doi: 10.1093/gerona/56.3.b130.J Gerontol A Biol Sci Med Sci. 2001.PMID: 11253150