1. Department of Epidemiology and Biostatistics; Michigan State University; East Lansing
2. Survey Research Center; University of Michigan; Ann Arbor
3. Department of Obstetrics and Gynecology; Wayne State University
4. Michigan Department of Community Health; Lansing; MI
5. Department of Public Health Sciences; Henry Ford Health System
6. Department of Obstetrics and Gynecology; Henry Ford Health System; Detroit