Submitted for Publication: July 19, 2013; final revision received September 23, 2013; accepted October 30, 2013.
Published Online: December 19, 2013. doi:10.1001/jamaoto.2013.6122.
Study concept and design: Richardson, Norris, Reed.
Acquisition of data: Richardson, Winford, Norris.
Analysis and interpretation of data: Richardson, Reed.
Drafting of the manuscript: Richardson, Winford.
Critical revision of the manuscript for important intellectual content: Richardson, Norris, Reed.
Statistical analysis: Richardson, Winford.
Administrative, technical, or material support: Norris.
Study supervision: Norris, Reed.
Conflict of Interest Disclosures: None reported.