Funding for this research was provided by:
Valdecilla National Research Award
Received: 15 January 2018
Accepted: 11 April 2018
First Online: 2 May 2018
Ethics approval and consent to participate
: Ethical approval was granted by the corresponding clinical research ethical committee of each center involved in the study [CitationRef removed] (University Hospital of Getafe, 06/26/2014; Puerta del Hierro-Majadahonda, 07/24/2014; Foundation Alcorcon, 11/03/2014; Fuenlabrada, 12/03/2014; Bellvitge, 09/10/2014; Salamanca, 07/18/2014; Navarra, 03/27/2015; Hospital Germans Trias i Pujol, 11/21/2014; and Cantabria 08/01/2014). All participants provided written informed consent after having been fully informed about the study aims.
: The authors declare no conflict of interest. The authors have full control of all primary data, and we agree to allow the journal to review the data if requested.
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