1Institute for Health and Aging, Department of Social and Behavioral Sciences, University of California, San Francisco, 3333 California Street, Suite 340, San Francisco, CA 94118 United States of America
2Health Division, Labour and Social Affairs, Organization for Economic Co-operation and Development, 2 rue Andre Pascal, Cedex 16, 75775 Paris, France
3School of Public Health, University of California, 635 E. Peltason Dr., 92697-3957 Irvine, CA United States of America
4School of Public Health, Goldman School of Public Policy, University of California, Berkeley, 50 University Hall MC7360, 94704 Berkeley, CA United States of America
© The Author(s). 2017
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