[1] Akershus Univ Hosp, Div Surg, Pelv Floor Ctr, Lorenskog, Norway
[2] Flinders Univ S Australia, Sch Med, Adelaide, SA 5001, Australia
[3] OsloMet Oslo Metropolitan Univ, Fac Hlth Sci, Oslo, Norway
[4] Oslo Univ Hosp, Res & Commun Unit Musculoskeletal Hlth, Oslo, Norway
[5] Drammens Gynaecol Private Clin, Drammen, Norway
[6] Norwegian Univ Sci & Technol, Dept Publ Hlth & Nursing, Trondheim, Norway
[7] Univ Oslo, Dept Biostat, Oslo, Norway
[8] Akershus Univ Hosp, Dept Obstet & Gynaecol, Lorenskog, Norway
[9] Univ Western Australia, Sch Populat & Global Hlth, Perth, WA, Australia