Submitted for Publication: January 23, 2011; final revision received July 18, 2011; accepted August 14, 2011.
Author Contributions: Dr Lee 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: Lee, Yeo, Kim, Woo, and S.-M. Jin. Acquisition of data: Lee, Yeo, Choi, and H.-J. Jin. Analysis and interpretation of data: Lee, Yeo, and S.-M. Jin. Drafting of the manuscript: Choi, H.-J. Jin, Kim, and Woo. Critical revision of the manuscript for important intellectual content: Lee, Yeo, and S.-M. Jin. Statistical analysis: Lee, Yeo, and Choi. Obtained funding: Lee and S.-M. Jin. Administrative, technical, and material support: Lee, Yeo, and S.-M. Jin. Study supervision: Lee, H.-J. Jin, Kim, Woo, and S.-M. Jin.
Financial Disclosure: None reported.
Funding/Support: This study was supported by the IN-SUNG Foundation for Medical Research, Seoul, South Korea.