1. Department of Gastrointestinal Surgery; Central Hospital of Central Finland; Jyväskylä; Finland
2. Department of Clinical Physiology; Tampere University Hospital; Tampere; Finland
3. Department of Respiratory Diseases; Central Hospital of Central Finland; Jyväskylä; Finland
4. Koskiklinikka; Tampere; Finland
5. STAT-Consulting; Nokia; Finland
6. Department of Surgery; Hatanpää Hospital; Tampere; Finland
7. Department of Respiratory Diseases; Tampere University Hospital; Tampere; Finland