1. Johns Hopkins University School of Nursing , 525 N Wolfe St., Baltimore, MD, 21205 USA
2. Institute of Nursing Science, Department of Public Health, University of Basel , Basel , Switzerland
3. University of Wollongong , NSW , Australia
4. Academic Centre for Nursing and Midwifery, Department of Public Health and Primary Care , KU, Leuven , Belgium
5. School of Nursing Nursing and Health Studies, University of Missouri-Kansas City , Missouri , USA