1. Department of Intensive Care, Hospital Universitario de Gran Canaria Dr. Negrín, Universidad de Las Palmas de Gran Canaria (ULPGC), Barranco de la Ballena s/n, 35010 Las Palmas de Gran Canaria, Spain
2. Department of Intensive Care, Hospital Universitario San Cecilio, A. del Conocimiento s/n, 18016 Granada, Spain
3. Department of Radiology, Hospital Universitario de Gran Canaria Dr. Negrín, Universidad de Las Palmas de Gran Canaria (ULPGC), Barranco de la Ballena s/n, 35010 Las Palmas de Gran Canaria, Spain
4. Department of Mathematics, Universidad de Las Palmas de Gran Canaria (ULPGC), 35010 Las Palmas de Gran Canaria, Spain
5. Department of Intensive Care, Hospital Clínico Universitario San Carlos, Calle del Prof. Martín Lagos s/n, 28040 Madrid, Spain
6. Department of Intensive Care, Hospital Clínico Universitario de Valladolid, Av. Ramón y Cajal 3, 47003 Valladolid, Spain
7. Department of Intensive Care, Hospital Universitario de Badajoz, Av.de Elvas s/n, 06080 Badajoz, Spain
8. Department of Intensive Care, Hospital Universitari de Terrassa: CST, Carr. De Torrebonica s/n, 08227 Terrassa, Spain
9. Department of Intensive Care, Hospital Regional Universitario de Málaga, Av. De Carlos Haya 84, 29010 Málaga, Spain
10. Department of Intensive Care, Hospital General Universitario de Castellón, Avinguda de Benicàssim 128, 12004 Castelló de la Plana, Spain
11. Department of Intensive Care, Hospital Universitari Dr Josep Trueta, Avinguda de França, s/n, 17007 Girona, Spain
12. Department of Intensive Care, Hospital Universitario Marqués de Valdecilla, Av. de Valdecilla s/n, 39008 Santander, Spain