1. Research Unit; Health Services Research on Chronic Patients Network (REDISSEC), Basurto University Hospital; Bilbao Spain
2. Unitat d'Epidemiologia; REDISSEC; Corporació Sanitària Parc Taulí; Sabadell REDISSEC Barcelona Spain
3. Public Health Unit. Seville Health District; CIBER of Epidemiology and Public Health-CIBERESP; Madrid Spain
4. REDISSEC, Research Unit. Donostia University Hospital/Biodonostia; San Sebastián Spain
5. Research Unit.; REDISSEC; Hospital of Galdakao; Usansolo Spain