[1] Columbia Univ, Coll Phys & Surg, New York, NY USA
[2] Georgetown Univ, Sch Med, Washington, DC USA
[3] Univ Colorado, Dept Dermatol, Aurora, CO USA
[4] Univ Colorado, Dept Epidemiol, Colorado Sch Publ Hlth, Aurora, CO USA
[5] Brown Univ, Dept Dermatol, Denver Dept Vet Affairs Hosp, Providence, RI 02912 USA
[6] Brown Univ, Dermatoepidemiol Unit, Dept Vet Affairs Med Ctr Providence, Providence, RI 02912 USA
[7] Brown Univ, Rhode Isl Hosp, Dept Dermatol, Providence, RI 02903 USA
[8] Brown Univ, Dept Dermatol & Epidemiol, Providence, RI 02912 USA