1. Medical Sociology, Department of Epidemiology and Preventive Medicine, University of Regensburg, Regensburg, Germany
2. Institute of Social Medicine and Health Systems Research, Medical Faculty, Otto von Guericke University Magdeburg, Magdeburg, Germany
3. Department of Gynecology and Obstetrics, Jane Fonda Center for Adolescent Reproductive Health, Emory University, Atlanta, GA, USA