Received: 21 June 2018
Accepted: 10 December 2018
First Online: 20 December 2018
Ethics approval and consent to participate
: All procedures performed were in accordance with the ethical standards of the institutional research committee of the Hospital Clinico San Carlos (San Carlos Ethics Research Committee, protocol 15/514-E), and with the 1964 Helsinki declaration and its later amendments. Written informed consent was obtained from all individual participants included in the study. All patients have the decision-making capacity preserved to consent for participating in the study, according to the ethics committee.
: Not applicable
: The authors declare that they have no competing interest.
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