1. Healthcare Centre (CS) Praza do Ferrol. Organizative Structure of Integrated Management (EOXI) Lugo; Cervo, e Monforte, Galician Health Service; Lugo Spain
2. Department of Surgery and Medical-Surgical Specialities, School of Medicine and Dentistry; University of Santiago de Compostela; A Coruña Spain
3. Unit of Research Methodology and Statistics, Ramón Domínguez Foundation for Research, Development and Innovation in Biomedical Research; Santiago de Compostela University Hospital, Galician Health Service. Santiago de Compostela; A Coruña Spain
4. Scientific and Technical Advice Unit; avalia-t. Galician Agency for Health Knowledge Management (ACIS); Santiago de Compostela Spain