Accepted for Publication: January 30, 2012.
Author Contributions: All authors had full access to all 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: Banerjee, Hay, and Greene. Acquisition of data: Banerjee and Greene. Analysis and interpretation of data: Banerjee and Hay. Drafting of the manuscript: Banerjee. Critical revision of the manuscript for important intellectual content: Banerjee, Hay, and Greene. Statistical analysis: Banerjee. Administrative, technical, and material support: Banerjee and Greene. Study supervision: Banerjee, Hay, and Greene.
Financial Disclosure: None reported.