[1] Univ Basel, Inst Nursing Sci, Bernoullistr 28, CH-4056 Basel, Switzerland
[2] Univ Zurich Hosp, Dept Abdomen Metab, Zurich, Switzerland
[3] Univ Zurich Hosp, Ctr Clin Nursing Sci, Zurich, Switzerland
[4] Univ Hosp Insel Bern, Insel Grp AG, Directorate Nursing MTT, Bern, Switzerland
[5] Hirslanden Grp, Ctr Sleep Med, Zollikon, Switzerland
[6] Univ Zurich Hosp, Dept Surg & Transplantat, Zurich, Switzerland
[7] Katholieke Univ Leuven, Acad Ctr Nursing & Midwifery, Dept Publ Hlth & Primary Care, Leuven, Belgium