Accepted for Publication: March 13, 2015.
Published Online: June 3, 2015. doi:10.1001/jamasurg.2015.1081.
Study concept and design: Lewis, Arterburn, Ross-Degnan, Gillman, Wharam.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: Lewis, Wharam.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Lewis, Zhang, Wharam.
Obtained funding: Lewis, Wharam.
Administrative, technical, or material support: Lewis, Gillman.
Study supervision: Lewis, Arterburn, Ross-Degnan, Gillman, Wharam.
Conflict of Interest Disclosures: None reported.
Funding/Support: This work was funded in part by a P30 grant from the National Institutes of Health (P30 HL101312; principal investigator, Dr Gillman).
Role of the Funder/Sponsor: The National Institutes of Health had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.