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Feldblum PJ, Bwayo JJ, Kuyoh M, Welsh M, Ryan KA, Chen-Mok M.Feldblum PJ, et al.Ann Epidemiol. 2000 Aug;10(6):339-46. doi: 10.1016/s1047-2797(00)00046-6.Ann Epidemiol. 2000.PMID: 10963999Clinical Trial.