Accepted for Publication: June 24, 2013.
Published Online: April 23, 2014. doi:10.1001/jamasurg.2013.3399.
Study concept and design: Zhou, Y. Wang, Hu.
Acquisition, analysis, or interpretation of data: Zhou, Zhang, Ruan, W.-J. Wang, Sun, Hu.
Drafting of the manuscript: Zhou.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Zhou, Zhang.
Administrative, technical, or material support: Y. Wang, Ruan, W.-J. Wang, Sun.
Study supervision: Hu.
Conflict of Interest Disclosures: None reported.
Correction: This article was corrected on June 16, 2014, to fix a typographical error in the title and Abstract.