Accepted for Publication: September 29, 2011.
Author Contributions: All authors had full access to all of 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: Mann. Acquisition of data: Mann. Analysis and interpretation of data: Duffy, Mann, Petronic-Rosic, and Shea. Drafting of the manuscript: Mann. Critical revision of the manuscript for important intellectual content: Duffy, Mann, Petronic-Rosic, and Shea. Administrative, technical, and material support: Mann. Study supervision: Duffy, Petronic-Rosic, and Shea.
Financial Disclosure: None reported.
Funding/Support: This study was supported in part by the Section of Dermatology, Department of Medicine, University of Chicago.
Role of the Sponsors: The sponsors had no role in the design and conduct of the study; in the collection, analysis, and interpretation of data; or in the preparation, review, or approval of the manuscript.
Additional Contributions: We are indebted to Yves Lussier for performing statistical analysis on the data.