1. Department of Pulmonology, Erasmus University Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
2. Department of Public Health, Erasmus University Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands.
3. Department of Pulmonary Medicine, University Hospital Gasthuisberg, Herestaat 49, 3000 Leuven, Belgium
4. Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
5. Center for Medical Imaging – North East Netherlands, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
6. Department of Public Health, Erasmus University Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands