Author Contributions: Study concept and design: Weinstock. Acquisition of data: Weinstock, Risica, and Kirtania. Analysis and interpretation of data: Markova, Weinstock, Risica, Kirtania, and Ombao. Drafting of the manuscript: Markova, Weinstock, and Ombao. Critical revision of the manuscript for important intellectual content: Markova, Weinstock, Risica, and Kirtania. Statistical analysis: Markova, Weinstock, Risica, Kirtania, and Ombao. Obtained funding: Weinstock. Administrative, technical, and material support: Markova and Weinstock. Study supervision: Weinstock and Risica.
Financial Disclosure: None reported.
Funding/Support: This study was supported by grant CA106592from the National Cancer Institute.
Previous Presentations: A version of this study was presented as a poster at the Society for Investigative Dermatology Annual Meeting; May 6, 2010; Atlanta, Georgia; and as an oral presentation at the American DermatoEpidemiology Network ancillary meeting; May 8, 2010; Atlanta.
Additional Contributions: The lead investigators at the 4 centers for this study were Christopher Chambers, MD (Mid-Atlantic—Center 1), Douglas Post, PhD (Central Ohio—Center 2), Ken Kallail, PhD (Kansas—Center 3), and Martin Kabongo, MD (Southern California—Center 4).