1. Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark;
2. The Robert Larner, M.D. College of Medicine at The University of Vermont, Burlington, VT, USA;
3. Breast Unit, Surgical Department, Randers Regional Hospital, Randers, Denmark;
4. Department of Oncology, Odense University Hospital, Odense, Denmark;
5. Institute of Clinical Research, University of Southern Denmark, Odense, Denmark;
6. Institute of Pathology, Aarhus University Hospital, Aarhus, Denmark;
7. Department of Plastic and Breast Surgery, Aarhus University Hospital, Aarhus, Denmark;
8. Danish Breast Cancer Cooperative Group, Copenhagen, Denmark;
9. Rigshospitalet, Copenhagen, Denmark;
10. Department of Health Research & Policy (Epidemiology), Stanford University, Stanford, CA, USA;
11. Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA;
12. Boston University School of Medicine, Boston University, Boston, MA, USA