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Machado EL, Caiaffa WT, César CC, Gomes IC, Andrade EI, Acúrcio Fde A, Cherchiglia ML.Machado EL, et al. Among authors: cesar cc.Cad Saude Publica. 2011;27 Suppl 2:S284-97. doi: 10.1590/s0102-311x2011001400015.Cad Saude Publica. 2011.PMID: 21789420Free article.