1. Department of Biostatistics and Epidemiology, College of Public Health,
2. Departments of Medicine and
3. Obstetrics & Gynecology, College of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, OK;
4. Department of Hematology and Central Hematology Laboratory, Inselspital, Berne University Hospital, University of Berne, Berne, Switzerland; and
5. Center for Thrombosis and Hemostasis, University Medical Center, Mainz, Germany