Published Online: May 26, 2015. doi:10.1001/jamainternmed.2015.2017.
Study concept and design: Song, Wallace, McWilliams.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: Song.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Song, Neprash, McKellar, Chernew.
Obtained funding: Song, McWilliams.
Administrative, technical, or material support: Wallace.
Study supervision: McWilliams.
Conflict of Interest Disclosures: None reported.
Funding/Support: Supported by grants from the National Institute on Aging (grant F30 AG039175) to Dr Song, from the Robert Wood Johnson Foundation/Health Care Financing Organization (grant 71408) to Drs McWilliams and Chernew, and from the National Science Foundation Graduate Research Fellowship (grant 1144152) to Mr Wallace.
Role of the Funder/Sponsor: The National Institute on Aging, the Robert Wood Johnson Foundation/Health Care Financing Organization, the National Science Foundation, and organizations with which the authors are affiliated had no role in the design and conduct of the study; in the collection, analysis, and interpretation of the data; in the preparation, review, or approval of the manuscript; or in the decision to submit the manuscript for publication.