[1] Univ Spital Basel, Dept Muskuloskelettales Syst, Basel, Switzerland
[2] Univ Zurich, Inst Epidemiol Biostat & Pravent, Zurich, Switzerland
[3] Univ Basel, Nursing Sci, Basel, Switzerland
[4] Maastricht Univ, Care & Publ Hlth Res Inst, Dept Hlth Serv Res, Maastricht, Netherlands
[5] Univ Spital Zurich, Zent Klin Pflegewissensch, Zurich, Switzerland
[6] Univ Spital Zurich, Klin Pneumologie, Zurich, Switzerland
[7] Univ Basel, Inst Pflegewissensch, Med Fak, Dept Publ Hlth, Bernoullistr 28, CH-4056 Basel, Switzerland