1. Departments of Medicine and Obstetrics & Gynecology; University of Michigan; Ann Arbor Michigan, USA
2. Department of Obstetrics & Gynecology; University of Michigan; Ann Arbor Michigan, USA
3. Department of Medicine; Johns Hopkins University; Baltimore Maryland, USA
4. Laval University
5. Department of Statistics; Purdue University; West Lafayette Indiana, USA
6. Dept. of Preventive Medicine; University of California; San Diego San Diego, California USA