1. Center for Social Epidemiology and Population Health Department of Epidemiology University of Michigan School of Public Health Ann Arbor USA
2. Survey Research Center Institute for Social Research University of Michigan Ann Arbor USA
3. MRC/Wits Rural Public Health & Health Transitions Research Unit (Agincourt) University of the Witwatersrand Johannesburg South Africa
4. Department of Psychiatry and Human Behavior Alpert Medical School Brown University Providence USA
5. Department of Neurology Alpert Medical School Brown University Providence USA
6. Department of Internal Medicine School of Medicine University of Michigan Ann Arbor USA
7. Institute for Healthcare Policy and Innovation University of Michigan Ann Arbor USA
8. Veterans Affairs Ann Arbor Center for Clinical Management Research Ann Arbor Michigan USA
9. Center for Economic and Social Research University of Southern California Los Angeles California USA
10. Department of Economics University of Southern California Los Angeles California USA
11. Sealy Center on Aging University of Texas Medical Branch Galveston Texas USA
12. Department of Epidemiology Johns Hopkins Bloomberg School of Public Health Baltimore USA