Received: 1 March 2016
Accepted: 29 December 2017
First Online: 12 January 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee for Research Project Analysis (CAPPesp), Clinicas Hospital, Faculty of Medicine, at the University of São Paulo (HC-FMUSP). Being a retrospective study, consent to participate was waived.
: Not applicable.
: The authors declare that they no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.