1. Department of Respiratory Medicine and Allergy, Karolinska University Hospital, Stockholm, Sweden
2. Respiratory Medicine Unit, Department of Medicine, Solna and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
3. Gävle Hospital, Gävle, Sweden
4. Skåne University Hospital, Malmö, Sweden
5. Department of Respiratory Medicine and Allergology, Skåne University Hospital, Lund University, Lund, Sweden
6. Sunderby Hospital, Luleå, Sweden