Received: 5 April 2017
Accepted: 27 June 2017
First Online: 25 July 2017
Ethics approval and consent to participate
: This study was authorized by the directors of the participating institutions and approved by the Research Ethics Committee of the Federal University of Sergipe (CAAE: 14,435,913.3.0000.5546). The collected data were for the exclusive use of the researchers having secured the confidentiality of information obtained in accordance with the resolution CNS n°. 466/2012.
: Not applicable.
: The authors declare that they have no competing interests.
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