1. Midwifery Research and Education Unit Hannover Medical School Hannover Germany
2. Department of Midwifery Research Institute of Health Sciences, Faculty of Medicine, University of Tübingen Tubingen Germany
3. Society for Quality in Out of Hospital Birth (QUAG) Hinter den Höfen 2 Storkow Germany
4. Department of Family Practice, Faculty of Medicine University of British Columbia 5950 University Boulevard Vancouver British Columbia Canada