Received: 7 December 2017
Accepted: 28 December 2017
First Online: 7 February 2018
Ethics approval and consent to participate
: The study was approved by the Ethic Committee of the IRCCS Neuromed, Pozzilli (Isernia), Italy, which designed and registered the study protocol (ClinicalTrials.gov ID: NCT02572219).
: Not applicable.
: The authors declare that they have no competing interests.
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