Funding for this research was provided by:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Received: 18 January 2018
Accepted: 26 February 2018
First Online: 6 March 2018
Ethics approval and consent to participate
: The project received approval from the Ethics Committee of the Clinical Hospital of the College of Medicine of the University of São Paulo (Comissão de Ética para Análise de Projetos de Pesquisa, CAPPesp, protocol number 1019/09).
: Not applicable. This is a retrospective study whose data were obtained from medical records and institutional databases.
: The authors declare that they have no competing interests.
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