Accepted for Publication: December 25, 2010.
Author Contributions: Dr Kawakami 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: Kawakami, Takeuchi, and Soma. Acquisition of data: Kawakami. Analysis and interpretation of data: Kawakami. Drafting of the manuscript: Kawakami and Takeuchi. Critical revision of the manuscript for important intellectual content: Kawakami and Soma. Obtained funding: Kawakami. Administrative, technical, and material support: Kawakami and Takeuchi. Study supervision: Kawakami and Soma.
Financial Disclosure: None reported.