1. Institute of Health and Nursing Sciences; Martin Luther University Halle-Wittenberg; Halle (Saale) Germany
2. Institute of Applied Nursing Science; Eastern Switzerland University of Applied Sciences (formerly FHS St. Gallen); St. Gallen Switzerland
3. Institute of Nursing Science, Faculty of Medicine and University Hospital Cologne; University of Cologne; Cologne Germany
4. Institute for Health Services Research and Health Economics, Centre for Health and Society, Medical Faculty and University Hospital Düsseldorf; Heinrich-Heine University; Düsseldorf Germany
5. School of Public Health; Bielefeld University; Bielefeld Germany