Accepted for Publication: July 19, 2013.
Published Online: September 23, 2013. doi:10.1001/jamainternmed.2013.10789.
Study concept and design: Likosky, Zhou, Malenka, Skinner.
Acquisition of data: Zhou, Skinner.
Analysis and interpretation of data: All authors.
Drafting of the manuscript: Likosky, Borden, Skinner.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Zhou, Skinner.
Obtained funding: Skinner.
Administrative, technical, and material support: Likosky, Zhou, Malenka.
Study supervision: Malenka.
Conflict of Interest Disclosures: Dr Skinner reported being a consultant to the National Bureau of Economic Research, receiving a grant from the Robert Wood Johnson Foundation, receiving payment for lectures from Cancer Clinics of Excellence and the Organisation for Economic Co-operation and Development, receiving travel expenses from the government of the Netherlands and the Congress of Neurological Surgeons, and serving on an advisory committee for Dorsata, Inc. Dr Borden reported serving as a senior advisor in the US Department of Health and Human Services, although his work on this study was not related to the US Department of Health and Human Services. Dr Likosky reported receiving a grant from the Agency for Healthcare Research and Quality. Dr Borden reported receiving support at Cornell University as a Nanette Laitman Clinical Scholar.
Funding/Support: This study was supported in part by grant P01-AG019783 from the National Institute on Aging, was conducted under Data Use Agreement 54913 between the Centers for Medicare & Medicaid Services and Dartmouth College, and has been approved by the Dartmouth Institutional Review Board.
Role of the Sponsor: None of the funders had a 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.