Funding for this research was provided by:
Associação Fundo de Incentivo à Pesquisa
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Centro Brasileiro de Informações Sobre Drogas Psicotrópicas
Received: 25 March 2018
Accepted: 2 November 2018
First Online: 22 November 2018
Ethics approval and consent to participate
: The project was approved by the ethics committee of UNIFESP (Protocol #0268/05), followed the recommendations for fieldwork and participation in the survey was voluntary, not obligatory. Participants were informed about the study objectives and consent was obtained prior to this study being carried out.
: Not applicable.
: The authors declare that they have no competing interests.
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