1. Institute of General Practice and Family Medicine, University of Witten/Herdecke, Witten, North-Rhine Westphalia, Germany
2. Department for Family-Oriented and Community-Based Nursing, Institute of Nursing Science, University of Witten/Herdecke, Witten, North-Rhine Westphalia, Germany
3. Research Department, Institute of General Practice and Family Medicine, Faculty of Medicine, University of Witten/Herdecke, Witten, North-Rhine Westphalia, Germany