1. Gastrointestinal Surgery; University of Helsinki; Helsinki University Hospital; Helsinki Finland
2. Unit of Primary Health Care; Helsinki University; Helsinki University Hospital; Helsinki Finland
3. Primary Health Care Unit; Department of General Practice; Kuopio University; Kuopio Finland
4. Research Department; The Social Insurance Institution of Finland; Turku Finland
5. Helsinki University Clinic of Gastroenterology; University of Helsinki; Helsinki Finland