Published Online: March 24, 2014. doi:10.1001/jamainternmed.2014.187.
Study concept and design: All authors.
Acquisition of data: Popova, Ling.
Analysis and interpretation of data: All authors.
Drafting of the manuscript: Grana, Popova.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Grana, Popova.
Obtained funding: Ling.
Study supervision: Ling.
Conflict of Interest Disclosures: None reported.
Funding/Support: Data originate from a study funded by the National Cancer Institute: R01-CA141661 (to L.P. and P.M.L.). R.A.G. is supported by Tobacco-Related Disease Research Program (TRDRP) grant 21FT-0040.
Role of the Sponsors: The funders 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.
Disclaimer: The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or TRDRP.