Funding for this research was provided by:
Instituto de Salud Carlos III (CM15/00102, INT16/00100, RD16/0025/0017, PI14/01094)
Text and Data Mining valid from 2018-04-11
Received: 8 August 2017
Accepted: 26 March 2018
First Online: 11 April 2018
Ethics approval and consent to participate
: The Ethics Committee of Hospital General Universitario Gregorio Marañón approved the study. The Committee waived the need for informed consent because the study was a retrospective chart review investigation that did not involve any risk to subjects, covered a prolonged period and because the requirement of individual consent would make the completion of the study impracticable.
: Not applicable
: The authors declare that they have no competing interests.
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