Funding for this research was provided by:
Instituto de Salud Carlos III (PS09/01770, PS09/00865, PS09/01129, PS09/01053)
Department of Health of Basque Government (2008111017)
Received: 6 September 2018
Accepted: 7 February 2019
First Online: 14 February 2019
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. This study received the approval of the following Ethics Committees for Clinical Research: Hospital Universitario de Basurto (22.08), Hospital Costa del Sol, Hospital Universitar Parc Taulí, and Hospital Universitario Nuestra Señora de Candelaria (09/09).Consent to participate was obtained from all individual participants included in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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