Accepted for Publication: September 14, 2011.
Published Online: January 2, 2012. doi:10.1001/archpediatrics.2011.1093. This article was corrected for errors on January 11, 2012.
Author Contributions: Ms Skoff had full access to all 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: Skoff, Cohn, Clark, Messonnier, and Martin. Acquisition of data: Skoff, Clark, and Martin. Analysis and interpretation of data: Skoff, Cohn, Clark, Messonnier, and Martin. Drafting of the manuscript: Skoff and Martin. Critical revision of the manuscript for important intellectual content: Cohn, Clark, Messonnier, and Martin. Statistical analysis: Skoff and Martin. Administrative, technical, and material support: Skoff and Clark. Study supervision: Clark, Messonnier, and Martin.
Financial Disclosure: None reported.
Additional Contributions: Kristin Brown, MPH, Grace Ejigiri, MPH, and Amanda Faulkner, MPH, of the CDC provided data management assistance during the analysis. Jennifer Liang, DVM, also of the CDC, provided scientific contributions.