Author Contributions: Dr Vitale 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: Vitale, Cotch, Sperduto.
Acquisition of data: Vitale, Cotch.
Analysis and interpretation of data: Vitale, Cotch, Sperduto.
Drafting of the manuscript: Vitale, Cotch.
Critical revision of the manuscript for important intellectual content: Vitale, Cotch, Sperduto.
Statistical analysis: Vitale.
Obtained funding: Cotch, Sperduto.
Administrative, technical, or material support: Cotch, Sperduto.
Financial Disclosures: None reported.
Funding/Support: This study was supported by the National Center for Health Statistics (NCHS), Centers for Disease Control and Prevention. Additional funding for the National Health and Nutrition Examination Survey (NHANES) Vision Component was provided by Intramural Research Program grant Z01EY000402 from the National Eye Institute, National Institutes of Health. The NCHS has contracted with Westat Inc to conduct the field operations and data collection for NHANES.
Role of the Sponsor: The NCHS was involved in the design and conduct of the study and in data collection, but was not involved in the analysis or interpretation of the vision examination study results or in the preparation, review, or approval of the manuscript. The National Eye Institute provided funding support for the vision examination and was involved in the design and conduct of the vision component, in the collection, analysis, and interpretation of the vision data, and in the preparation, review, and approval of this article before submission.
Acknowledgment: We thank the staff of the NCHS, Centers for Disease Control and Prevention, especially Brenda G. Lewis, BS, ASCP, MPH, for their expert assistance with all technical aspects of the vision component. Ms Lewis received salary compensation from NCHS. We also thank the staff at Westat Inc, especially Kay Apodaca, BA, MSW, and Beryl D. Carew, MPH, BN, for their role with data collection activities. Mss Apodaca and Carew received salary compensation from their employer, Westat Inc (contracted by NCHS). We thank Susan K. Corwin, BSMA, CO, COMT, Director of Training and Education for Marco. Ms Corwin was paid by Westat Inc, for her role as a consultant in training the NHANES field staff technicians in the use of the Marco/Nidek equipment. We also thank Roy W. Beck, MD, PhD, Jaeb Center for Health Research, for technical advice in designing the NHANES vision component protocol. Dr Beck did not receive compensation for his role in the study. We are grateful to all the people who agreed to participate in NHANES, without whose time and dedication this study would not have been possible.