Funding for this research was provided by:
Instituto de Salud Carlos III (2007/05)
Department of Health of the Basque Government (2011111091)
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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