Submitted for Publication: July 26, 2013; final revision received October 2, 2013; accepted October 14, 2013.
Published Online: January 23, 2014. doi:10.1001/jamaophthalmol.2013.7682.
Study concept and design: Gibson.
Acquisition of data: Gibson.
Analysis and interpretation of data: Gibson.
Drafting of the manuscript: Gibson.
Critical revision of the manuscript for important intellectual content: Gibson.
Statistical analysis: Gibson.
Obtained funding: Gibson.
Conflict of Interest Disclosures: None reported.
Funding/Support: This research was supported by grant 64099-00 42 from The City University of New York Professional Staff Congress–City University of New York Research Award Program (Dr Gibson).
Role of the Sponsor: The funding source had no role in the design and conduct of the study; collection, management, analysis, or interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Disclaimer: The findings and conclusions in this article are those of the author and do not necessarily represent the views of the NCHS, Centers for Disease Control and Prevention.
Additional Information: The use of restricted-access data for this project was approved by the National Center for Health Statistics (NCHS), Centers for Disease Control and Prevention. All results presented in the article have been cleared for release by the NCHS Research Data Center.
Additional Contributions: Gerald Cubbin, PhD, provided helpful suggestions for improving the article.