Author Contributions: Dr Madden had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Madden, Zhang, Adams, Briesacher, Ross-Degnan, Gurwitz, Safran, Soumerai.
Acquisition of data: Madden, Pierre-Jacques, Safran, Adler, Soumerai.
Analysis and interpretation of data: Madden, Graves, Zhang, Adams, Briesacher, Ross-Degnan, Gurwitz, Pierre-Jacques, Safran, Soumerai.
Drafting of the manuscript: Madden, Soumerai.
Critical revision of the manuscript for important intellectual content: Madden, Graves, Zhang, Adams, Briesacher, Ross-Degnan, Gurwitz, Pierre-Jacques, Safran, Adler, Soumerai.
Statistical analysis: Madden, Graves, Zhang, Pierre-Jacques.
Obtained funding: Madden, Zhang, Adams, Breisacher, Ross-Degnan, Gurwitz, Safran, Soumerai.
Administrative, technical, or material support: Madden, Graves, Pierre-Jacques, Safran, Adler, Soumerai.
Study supervision: Madden, Soumerai.
Financial Disclosures: Drs Madden and Adams, and Ms Pierre-Jacques report receiving research support from AstraZeneca. Drs Zhang, Adams, Ross-Degnan, and Soumerai, and Ms Graves report receiving research support from Eli Lilly. Dr Zhang also reports receiving research support from Pfizer and Sanofi-Aventis. Dr Briesacher reports receiving research support and consulting fees from Novartis. Dr Gurwitz reports receiving research support from GlaxoSmithKline. Dr Safran and Mr Adler did not report any financial disclosures.
Funding/Support: This study was supported by grants R01AG028745 and R01AG022362 from the National Institute on Aging (NIA), and the Harvard Pilgrim Health Care Foundation. Drs Zhang, Briesacher, Ross-Degnan, Gurwitz, and Soumerai are investigators in the Health Maintenance Organization Research Network Center for Education and Research in Therapeutics, which is supported by grant 2U18HS010391 from the US Agency for Healthcare Research and Quality.
Role of the Sponsor: The funding organizations did not participate in the design or conduct of the study, in the collection, analysis, or interpretation of the data, or in the preparation, review, or approval of the manuscript.
Additional Contributions: Franklin Eppig, JD (Centers for Medicare & Medicaid Services [CMS]), integrated measures of cost-related medication nonadherence into the Medicare Current Beneficiary Survey (MCBS), and Andrew Shatto, BS (CMS), provided assistance with data access and definition. Michael Law, MSc (Harvard Medical School [HMS] and Harvard Pilgrim Health Care [HPHC]), provided helpful advice on modeling strategies; Alan Zaslavsky, PhD (HMS), and Ken Kleinman, ScD (HMS and HPHC), both provided statistical advice; and Robert LeCates, MA (HMS and HPHC), provided assistance during manuscript preparation. Mr LeCates’ salary was partially supported by the NIA grants mentioned above. All others mentioned did not receive any direct compensation.