Received: 28 January 2018
Accepted: 23 May 2018
First Online: 7 June 2018
Ethics approval and consent to participate
: This research received ethical approval from the Federal University of Sao Paulo (UNIFESP) ethics committee under the protocol number 20221013.9.0000.5505. The mother or the father of the child provided written informed consent for participation prior to data collection.
: The authors declare that they have no competing interests.
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