1. Swiss Centre of Expertise in Life Course Research, Faculty of Social and Political Sciences, University of Lausanne, Lausanne CH 1015, Switzerland
2. Robert N. Butler Columbia Aging Center, Mailman School of Public Health, Columbia University, New York, NY 10032
3. Department of Sociology, Princeton University, Mercer, NJ 08544
4. Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden ZC 2333, Netherlands
5. Institute for Social Research, University of Michigan at Ann Arbor, Ann Arbor, MI 48106
6. Department of Epidemiology, Columbia University Mailman School of Public Health, New York, NY 10032
7. Department of Biostatistics, Columbia University Mailman School of Public Health, New York, NY 10032
8. Center for Demography and Ecology, Robert M. La Follette School of Public Affairs, University of Wisconsin-Madison, Madison, WI 53706