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Hernández-Díaz S, Martínez-Losa E, Fernández-Jarne E, Serrano-Martínez M, Martínez-González MA.Hernández-Díaz S, et al.Epidemiology. 2002 Nov;13(6):700-6. doi: 10.1097/00001648-200211000-00015.Epidemiology. 2002.PMID: 12410012