1. IRCCS Istituto Auxologico Italiano, Milan, Italy (M.F.P., A.F., C.L., G.P.).
2. Sleep Disorders Center, Respiratory Medicine, Sahgrenska University Hospital, Gothenburg, Sweden (L.G.).
3. Department of Internal Medicine and Cardiology, University Hospital Brno (O.L.).
4. University Hospital L. Pasteur Košice - Univerzitná nemocnica L. Pasteura Košice, Slovakia (P.J.).
5. Department of Respiratory Medicine, Respiratory Failure Unit, G.Papanikolaou Hospital, Aristotle University of Thessaloniki, Greece (A.P.).
6. Sleep Medicine Center, Department of Neurosciences, University of Split School of Medicine, Split, Croatia (Z.D.).
7. Department of Pulmonology, CardioPrevent Foundation, University of Medicine and Pharmacy Victor Babes Timisoara, Romania (S.M.).
8. Sleep Disorders Center, Reinbeck, Germany (H.H.).
9. Division of Medicine, Department of Pulmonary Diseases, Turku University Hospital, University of Turku, Finland (U.A.).
10. Pulmonary and Sleep Disorders Unit, St Vincent’s University Hospital and School of Medicine, University College Dublin, Ireland (S.R.).
11. Department of Medicine and Surgery, University of Milan-Bicocca, Italy (C.L., G.P.).