Funding for this research was provided by:
Insituto de Salud Carlos III (PI17/00581)
Received: 7 May 2018
Accepted: 18 October 2018
First Online: 12 November 2018
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.
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