Text and Data Mining valid from 2018-04-05
Received: 26 January 2017
Accepted: 21 March 2018
First Online: 5 April 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Hospital de Santo António, Oporto Hospital Centre, Portugal, and informed consent was waived due to the observational nature of the study.
: Not applicable
: The authors declare that they have no competing interests.
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