1. Department of Health and Human Development, University of Pittsburgh, Pittsburgh, USA
2. Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA, USA
3. Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, USA
4. Department of Epidemiology, University of Michigan, Ann Arbor, MI, USA
5. Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
6. Department of Psychology, University of Pittsburgh, Pittsburgh, PA, USA
7. Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
8. Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA