1. Primary Health Care of the Capital Area , Reykjavik , Iceland
2. Faculty of Medicine, University of Iceland , Reykjavik , Iceland
3. Sleep Department, Landspitali, The National University Hospital of Iceland , Reykjavik , Iceland
4. Division of Sleep Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania , Philadelphia, PA , USA
5. Department of Medicine, Corporal Michael J. Crescenz VA Medical Center , Philadelphia, PA , USA
6. Interdisciplinary Center of Sleep Medicine, Charité University Hospital , Berlin , Germany
7. Department of Respiratory Medicine, Peking University People’s Hospital , Beijing , China
8. Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
9. Department of Respiratory and Sleep Medicine, Royal North Shore Hospital , St Leonards NSW , Australia
10. Northern Clinical School and Charles Perkins Centre, University of Sydney , Camperdown NSW , Australia
11. Division of Pulmonary, Critical Care, and Sleep Medicine, The Ohio State Wexner Medical Center , Columbus, OH , USA
12. Sir Charles Gairdner Hospital, Western Australian Sleep Disorders Research Institute , Nedlands, Western Australia , Australia
13. Faculty of Human Sciences, University of Western Australia , Crawley, Western Australia , Australia