Accepted for Publication: November 14, 2012.
Published Online: February 18, 2013. doi:10.1001/jamainternmed.2013.3271
Author Contributions: Dr Ake and Mss Inacio and Paxton 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: Paxton, Khatod, Wang, Marinac-Dabic, Gross, Kaczmarek, and Sedrakyan. Acquisition of data: Inacio and Paxton. Analysis and interpretation of the data: Inacio, Ake, Paxton, Khatod, Wang, Marinac-Dabic, Gross, Kaczmarek, and Sedrakyan. Drafting of the manuscript: Inacio and Ake. Critical revision of the manuscript for important intellectual content: Paxton, Khatod, Wang, Marinac-Dabic, Gross, Kaczmarek, and Sedrakyan. Statistical analysis: Ake. Obtaining funding: Paxton.Administrative, technical and material support: Inacio. Study supervision: Inacio, Paxton, Khatod, Wang, Marinac-Dabic, Gross, Kaczmarek, and Sedrakyan.
Conflict of Interest Disclosures: Alan L. Schepps, MS, is employed by the Surgical Outcomes and Analysis Department and received no additional compensation for contributing to the manuscript.
Funding/Support: This study was funded by contract HHSF22200860493P from the Division of Epidemiology, Office of Surveillance and Biometrics, Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, Maryland.
Role of the Sponsors: The Division of Epidemiology of the US Food and Drug Administration participated in the design and conduct of the study, interpretation of the data, and review and approval of the manuscript.
Additional Contributions: Alan L. Schepps, MS, provided support with the statistical data programming, tables, and graphs prepared for the manuscript. We acknowledge all the Kaiser Permanente orthopaedic surgeons who contribute to the TJRR and the Surgical Outcomes and Analysis Department, which coordinates registry operations.