Published Online: June 12, 2011. doi:10.1001/jama.2011.811
Author Contributions: Dr Shen 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, acquisition of data, critical revision of the manuscript for important intellectual content, and administrative, technical, or material support: Shen, Hsia.
Analysis and interpretation of data, drafting of the manuscript, statistical analysis, obtained funding, and study supervision: Shen.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.
Funding/Support: This work was supported by grant 63974 from the Robert Wood Johnson Foundation's Changes in Health Care Financing and Organization initiative (Dr Shen), grant KL2 RR024130 from the National Institutes of Health/National Center for Research Resources, University of California, San Francisco Clinical and Translational Science (Dr Hsia), and the Robert Wood Johnson Foundation Physician Faculty Scholars (Dr Hsia).
Role of the Sponsors: The sponsors had no role in the design and conduct of the study, in the collection, management, analysis, and interpretation of the data, or in the preparation, review, or approval of the manuscript.
Disclaimer: The article contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Institutes of Health or the Robert Wood Johnson Foundation.
Additional Contributions: Laurence Baker, PhD (Stanford University, Palo Alto, California), provided constructive suggestions throughout the project; Jean Roth, MA (National Bureau of Economic Research, Cambridge, Massachusetts), assisted with obtaining and extracting the patient data; Shoutzu Lin, MS (Veterans Affairs, Menlo Park, California), provided excellent programming assistance; and Tiffany Wang, BA (University of California, San Francisco), provided technical assistance. None received additional compensation other than university salary for their contributions.