[1] Univ Stavanger, Fac Hlth Sci, Dept Publ Hlth, N-4036 Stavanger, Norway
[2] Stavanger Univ Hosp, Res Dept, Res Grp Nursing & Hlth Sci, Stavanger, Norway
[3] Stavanger Univ Hosp, Dept Gastrointestinal Surg, Stavanger, Norway
[4] Univ Bergen, Dept Clin Med, Bergen, Norway
[5] Molde Univ Coll, Fac Hlth Sci & Social Care, Molde, Norway
[6] Univ Southampton, Sch Hlth Sci, NIHR CLAHRC Wessex, Bldg 67,Highfield Campus,Univ Rd, Southampton SO17 1BJ, England
[7] Univ Hosp Southampton NHS Fdn Trust, Southampton Gen Hosp, Mailpoint 11,Clin Acad Facil,Room AA102,South Acad, Southampton SO16 6YD, England
[8] Univ Stavanger, Fac Hlth Sci, Dept Qual & Hlth Technol, N-4036 Stavanger, Norway
[9] VID Specialized Univ, Fac Hlth Studies, Oslo, Norway
[10] Western Norway Univ Appl Sci, Dept Hlth & Caring Sci, Stord, Norway