Author Contributions: Dr B. E. K. Klein 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: B. E. K. Klein, R. Klein.
Acquisition of data: B. E. K. Klein, Dreyer, R. Klein.
Analysis and interpretation of data: B. E. K. Klein, Howard, Gangnon, Lee.
Drafting of the manuscript: B. E. K. Klein, Howard.
Critical revision of the manuscript for important intellectual content: B. E. K. Klein, Howard, Gangnon, Dreyer, Lee, R. Klein.
Statistical analysis: Howard, Gangnon, Lee.
Obtained funding: B. E. K. Klein, R. Klein.
Administrative, technical, or material support: B. E. K. Klein, Dreyer, R. Klein.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr R. Klein reported serving as a consultant to Pfizer. No other authors reported disclosures.
Funding/Support: This study was supported by National Institutes of Health (NIH) grant EY06594 (Drs B. E. K. Klein, R. Klein). The National Eye Institute provided funding for the entire study, including for collection and analyses of data. Additional support was provided by Senior Scientific Investigator Awards from Research to Prevent Blindness (Drs B. E. K. Klein, R. Klein).
Role of the Sponsor: The funding organizations had no role in the design and conduct of the study; the collection, management, analysis, and interpretation of the data; or the preparation, review, or approval of the manuscript.
Disclaimer: The content of this article is solely the responsibility of the authors and does not necessarily reflect the official views of the National Eye Institute or the NIH.
Additional Contributions: Heidi M. G. Christian, BA, and Mary Kay Aprison, BS, of the Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, assisted with technical editing and preparation of the manuscript. They received no additional compensation beyond their normal wages as employees of the University of Wisconsin for their assistance.
This article was corrected for errors on December 19, 2012.