Funding for this research was provided by:
Instituto de Salud Carlos III (PI17/00581)
Received: 27 June 2019
Accepted: 13 February 2020
First Online: 19 February 2020
Ethics approval and consent to participate
: The local ethical committee of the “Complejo Hospitalario de Toledo” gave approval to the study and warranted its accordance with the Declaration of Helsinki (number 158; 2-11-2017). Written informed consent was obtained from all participants prior to participation.
: Not applicable.
: Avendaño-Coy, Taylor and Gómez-Soriano have a patent of a device which evokes electrical current between 10 kHz and 50 kHz, although this device has not used in this work. The remaining authors have no conflicts of interest.