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Arango E, Maestre A, Carmona-Fonseca J.Arango E, et al.Rev Bras Epidemiol. 2010 Sep;13(3):373-86. doi: 10.1590/s1415-790x2010000300002.Rev Bras Epidemiol. 2010.PMID: 20857025Free article.Review.Spanish.