Article History
Received: 23 March 2018
Accepted: 11 July 2018
First Online: 9 August 2018
Ethics approval and consent to participate
: The study was submitted to the Comitato Etico Interaziendale di Novara (ExternalRef removed), which reviewed it and awarded an exemption letter (protocol number 713/CE).
: Not applicable
: The authors declare that they have no competing interests.
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