Funding for this research was provided by:
Instituto de Salud Carlos III (TPY1238/15)
Ministerio de Educación, Cultura y Deporte (FPU14/03914)
Text and Data Mining valid from 2019-04-08
Received: 31 January 2019
Accepted: 1 April 2019
First Online: 8 April 2019
Ethics approval and consent to participate
: The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the Ethics Committee of the Instituto de Salud Carlos III (CEI 50/2013).
: Not applicable.
: The authors declare that they have no competing interests.
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