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Boyle CA, Yeargin-Allsopp M, Schendel DE, Holmgreen P, Oakley GP.Boyle CA, et al.Am J Epidemiol. 2000 Jul 15;152(2):120-4. doi: 10.1093/aje/152.2.120.Am J Epidemiol. 2000.PMID: 10909948