Accepted for Publication: August 20, 2014.
Published Online: December 22, 2014. doi:10.1001/jamapediatrics.2014.2320.
Study concept and design: Gibson, Herring, Kutcher, Broglio.
Acquisition, analysis, or interpretation of data: Gibson, Kutcher, Broglio.
Drafting of the manuscript: All authors.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Gibson.
Obtained funding: Gibson.
Administrative, technical, or material support: Gibson.
Study supervision: Gibson, Herring, Kutcher.
Conflict of Interest Disclosures: None reported.
Funding/Support: This investigation was supported in part by Truven Health from the National Institute of Child Health and Human Development (Dr Gibson).
Role of the Funder/Sponsor: The funding source 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.
Additional Contributions: Gary Allen, MS, Truven Health Analytics, provided programming assistance, Melina Imshaug, BA, Truven Health Analytics, provided research assistance, and Andrew M. Bernard Jr, CPA, a former high school football coach, contributed assistance with the manuscript. We also thank seminar participants at Harvard Medical School, the Centers for Disease Control and Prevention, and Pennsylvania State University for their helpful comments and feedback. Mr Allen and Ms Imshaug contributed to the study through their affiliation with Truven Health Analytics and received financial compensation. No others received financial compensation.