1. InsStitute of Social Medicine and Health Economics Otto von Guericke University Magdeburg Magdeburg Germany
2. Medical Sociology Department of Epidemiology and Preventive Medicine University of Regensburg Regensburg Germany
3. Ann and Robert H. Lurie Children’s Hospital of Chicago and Northwestern Feinberg School of Medicine Chicago IL USA
4. Department of Medical Social Sciences Feinberg School of Medicine Northwestern University Chicago IL USA