Accepted for Publication: February 27, 2013.
Published Online: August 28, 2013. doi:10.1001/jamasurg.2013.3393.
Acquisition of data: All authors.
Analysis and interpretation of data: All authors.
Drafting of the manuscript: All authors.
Critical revision of the manuscript for important intellectual content: All authors.
Administrative, technical, and material support: Neumayer.
Study supervision: Neumayer.
Conflict of Interest Disclosures: None reported.
Correction: This article was corrected on November 11, 2013, to fix an inaccurate number in the text.