Text and Data Mining valid from 2019-05-22
Received: 28 January 2019
Revised: 25 March 2019
Accepted: 1 May 2019
First Online: 22 May 2019
Compliance with ethical standards
: Sánchez-González, José-María declares that he has no conflict of interest. Alonso-Aliste, Federico declares that he has no conflict of interest.
: 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.
: Informed consent was obtained from all individual participants included in the study.