Author Contributions: Dr Bishop had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Bishop, Casalino.
Acquisition of data: Bishop.
Analysis and interpretation of data: Bishop, Ryan, Casalino.
Drafting of the manuscript: Bishop, Casalino.
Critical revision of the manuscript for important intellectual content: Bishop, Ryan, Casalino.
Statistical analysis: Bishop, Ryan.
Administrative, technical, or material support: Bishop.
Study supervision: Casalino.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.
Funding/Support: Dr Bishop is supported in part by funds provided to her as a Nanette Laitman Clinical Scholar in Public Health at Weill Cornell Medical College. Dr Ryan is supported by grant K01 HS018546-01 from the Agency for Healthcare Research and Quality.
Role of the Sponsor: The funding organizations had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; or preparation, review, or approval of the manuscript.
This article was corrected for errors on June 23, 2011.