1. Research Unit of Population Health, Faculty of Medicine, University of Oulu , Oulu, Finland
2. Medical Research Center Oulu, Oulu University Hospital and University of Oulu , Oulu, Finland
3. Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht and Utrecht University , Utrecht, The Netherlands
4. Department of Economics, Oulu Business School, University of Oulu , Oulu, Finland
5. Research Unit of Health Sciences and Technology, University of Oulu , Oulu, Finland