[1] Oslo Univ Hosp, Res & Commun Unit Musculoskeletal Hlth FORMI, Oslo, Norway
[2] Oslo Metropolitan Univ, Dept Physiotherapy, Fac Hlth Sci, Oslo, Norway
[3] Norwegian Univ Sci & Technol, Dept Publ Hlth & Nursing, Fac Med & Hlth Sci, Trondheim, Norway
[4] Norwegian Univ Sci & Technol, Fac Social & Educ Sci, Dept Psychol, Trondheim, Norway
[5] Norwegian Univ Sci & Technol, Dept Publ Hlth & Nursing, Gen Practice Res Unit, Fac Med & Hlth Sci, Trondheim, Norway