1. Department of Social Sciences and Health Policy, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
2. Tan Chingfen Graduate School of Nursing, UMass Chan Medical School, Worcester, Massachusetts, USA.
3. Department of Internal Medicine, Spencer Fox Eccles School of Medicine, University of Utah, Salt Lake City, Utah, USA.
4. Department of Epidemiology, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, USA.
5. School of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA.
6. Department of Obstetrics and Gynecology, School of Medicine, University of California Davis, Sacramento, California, USA.