Published Online: February 11, 2013. doi:10.1001/jamainternmed.2013.2509
Author Contributions: Dr Zhang and Mr Wu had full access to all 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: Zhang, Fendrick, and Baicker. Acquisition of data: Zhang and Wu. Analysis and interpretation of data: Zhang, Wu, Fendrick, and Baicker. Drafting of the manuscript: Zhang and Wu. Critical revision of the manuscript for important intellectual content: Zhang, Fendrick, and Baicker. Statistical analysis: Zhang, Wu, and Baicker. Obtained funding: Zhang. Administrative, technical, and material support: Zhang. Study supervision: Zhang and Fendrick.
Conflict of Interest Disclosures: Dr Baicker is a Commissioner on the Medicare Payment Advisory Commission and a director of Eli Lilly.
Funding/Support: This study was supported by grant HHSP22320042509XI from the Institute of Medicine, grant RC1 MH088510 from the National Institute of Mental Health, and grant R01 HS018657 from the Agency for Healthcare Research and Quality (Dr Zhang).
Previous Presentation: Some preliminary results from this study were presented at the closed session meetings to the Institute of Medicine committee in Geographic Variation in Health Care Spending and Promotion of High-Value Care; June 4, 2012; Washington, DC.