[1] Turku Univ Hosp, Div Digest Surg & Urol, Dept Acute, FIN-20520 Turku, Finland
[2] Turku Univ Hosp, Div Digest Surg & Urol, Dept Digest Surg, FIN-20520 Turku, Finland
[3] Turku Univ, Dept Surg, Turku, Finland
[4] Mikkeli Cent Hosp, Dept Surg, Mikkeli, Finland
[5] Univ Eastern Finland, Inst Clin Med, Joensuu, Finland
[6] Oulu Univ Hosp, Dept Surg, Oulu, Finland
[7] Tampere Univ Hosp, Div Surg Gastroenterol & Oncol, Tampere, Finland
[8] Jyvaskyla Cent Hosp, Dept Surg, Jyvaskyla, Finland
[9] Kuopio Univ Hosp, Dept Surg, SF-70210 Kuopio, Finland
[10] Seinajoki Cent Hosp, Dept Surg, Seinajoki, Finland
[11] Univ Turku, Dept Publ Hlth, Turku, Finland
[12] Hosp Dist Southwest Finland, Primary Hlth Care Unit, Turku, Finland
[13] Univ Turku, Dept Biostat, Turku, Finland
[14] Turku Univ Hosp, Dept Radiol, FIN-20520 Turku, Finland
[15] Oulu Univ Hosp, Dept Radiol, Oulu, Finland
[16] Tampere Univ Hosp, Dept Radiol, Tampere, Finland