Author Contributions: Drs Marmot, Banks, and Smith and Ms Oldfield had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Banks, Marmot, Oldfield, Smith.
Acquisition of data: Banks, Marmot, Oldfield, Smith.
Analysis and interpretation of data: Banks, Marmot, Oldfield, Smith.
Drafting of the manuscript: Banks, Marmot, Oldfield, Smith.
Critical revision of the manuscript for important intellectual content: Banks, Marmot, Oldfield, Smith.
Statistical analysis: Banks, Oldfield, Smith.
Obtained funding: Banks, Marmot, Smith.
Administrative, technical, or material support: Banks, Oldfield, Smith.
Study supervision: Banks, Marmot, Smith.
Financial Disclosures: None reported.
Funding/Support: The research was supported by a grant from the US National Institute on Aging (NIA) to RAND and from the NIA and the Economic and Social Research Council to the Institute for Fiscal Studies. The English Longitudinal Study on Ageing has been supported by grants 2RO1AG7644-01A1 and 2RO1AG017644 from the NIA and several British government departments, specifically, the Department for Education and Skills; Department for Environment, Food, and Rural Affairs; Department of Health; Department of Trade and Industry; Department for Work and Pensions; the HM Treasury Inland Revenue; the Office of the Deputy Prime Minister; and the Office for National Statistics. Dr Marmot is supported by a Medical Research Council Research Professorship. Dr Banks and Ms Oldfield's research was supported by grant P01 Ag008291-13 from the US NIA with cofunding from grant M544285003 from the Economic and Social Research Council through the Center for the Microeconomic Analysis of Public Policy at the Institute of Fiscal Studies. Dr Smith was supported by grant P01 AG008291-13 from the NIA. Funding for the Health and Retirement Study was provided by grant U01AG009740 from the NIA.
Role of the Sponsors: The funding organizations had no role in the design and conduct of the study, collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript.