Author Contributions: Mr Alpert 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: Connolly, Alpert.
Acquisition of data: Alpert.
Analysis and interpretation of data: Connolly, Alpert.
Drafting of the manuscript: Connolly, Alpert.
Critical revision of the manuscript for important intellectual content: Connolly, Alpert.
Statistical analysis: Alpert.
Obtained funding: Connolly.
Administrative, technical, or material support: Connolly.
Financial Disclosures: Dr Connolly and Mr Alpert reported having received funding from the National Cancer Institute, Flight Attendants Medical Research Institute, and American Legacy Foundation, unrelated to this study.
Funding/Support: Funding was provided by the American Legacy Foundation, which was created by and is currently funded by the Tobacco Master Settlement Agreement.
Role of the Sponsor: The American Legacy Foundation had no role in the design and conduct of the study; in the collection, analysis, and interpretation of the data; or in the preparation, review, or approval of the manuscript.
Additional Contributions: Ron Spalletta, BA, Harvard School of Public Health, provided data assistance, for which he was compensated.