1. Department of Care Science, Faculty of Health and Society, Malmö University, Malmö, Sweden
2. Department of Internal Medicine and Clinical Nutrition, Krefting Research Centre and Environmental and Occupational Medicine, University of Gothenburg, Gothenburg, Sweden
3. Halland Region, Kungsbacka Health Centre, Kungsbacka, Sweden
4. Research and Development, Obstructive Lung Disease In Northern Sweden (OLIN) Studies, Norrbotten County Council, Luleå, Sweden
5. Department of Public Health and Clinical Medicine, Division of Occupation and Environment/The OLIN Unit, University of Umeå, Umeå, Sweden