Received: 13 December 2017
Accepted: 19 February 2018
First Online: 13 April 2018
Ethics approval and consent to participate
: This study was approved by our Institutional Research Ethics Committee de la Fundació UNIO CATALANA HOSPITALS (reference number: CEIC 11/23). It has also approved by the local ethics committees, in accordance with Spanish regulations.
: All authors read and approved the final manuscript. This study was approved by our Institutional Department of Investigation in accordance with Spanish regulations.
: The authors declare that they have no competing interests.
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