[1] Univ S Carolina, Sch Med, Columbia, SC USA
[2] Columbia Univ Coll Phys & Surg, New York, NY 10032 USA
[3] Georgetown Univ, Sch Med, Washington, DC USA
[4] VA Med Ctr Providence, Dermatoepidemiol Unit, Providence, RI USA
[5] Rhode Isl Hosp, Dept Dermatol, Providence, RI USA
[6] Brown Univ, Dept Dermatol, Providence, RI 02912 USA
[7] Brown Univ, Dept Epidemiol, Providence, RI 02912 USA
[8] Yale Univ, Sch Med, Robert Wood Johnson Fdn Clin Scholars Program, New Haven, CT USA
[9] Connecticut Hlth Care Syst, US Dept Vet Affairs, Dermatol Serv, West Haven, CT USA
[10] Kings Coll Hosp NHS Trust, Dept Dermatol, London, England
[11] Univ Washington, Inst Hlth Metr & Evaluat, Seattle, WA 98195 USA
[12] Childrens Natl Med Ctr, Dermatol Div, Washington, DC 20010 USA
[13] Azienda Osped Papa Giovanni XXIII, Dept Dermatol, Bergamo, Italy
[14] Univ Colorado, Dept Dermatol, Aurora, CO 80045 USA
[15] Colorado Sch Publ Hlth, Dept Epidemiol, Aurora, CO USA
[16] Eastern Colorado Hlth Care Syst, US Dept Vet Affairs, Dermatol Serv, Denver, CO 80220 USA