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Article History

Received: 10 June 2016

Accepted: 21 January 2018

First Online: 8 February 2018

Ethics approval and consent to participate

: This trial was approved by the Clinical Research Ethics Committee of the Basque Country (acta 6/2008). This Committee approved the protocol considering that patient informed consent was not required due to the cluster design of the study and the anonymization of patients data.

: Not applicable

: The authors declare that they have no competing interests.

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