[1] Univ Hlth Network, Div Dermatol, Toronto, ON, Canada
[2] Warren Alpert Med Sch, Dept Dermatol, Providence, RI 02903 USA
[3] Brown Univ, Sch Publ Hlth, Dept Epidemiol, Providence, RI 02912 USA
[4] Brigham & Womens Hosp, Dept Med, Channing Div Network Med, 75 Francis St, Boston, MA 02115 USA
[5] Harvard Univ, Sch Med, Boston, MA 02115 USA
[6] Massachusetts Gen Hosp, Dept Emergency Med, Boston, MA 02114 USA
[7] Harvard Univ, TH Chan Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA
[8] Rhode Isl Hosp, Dept Dermatol, Providence, RI 02903 USA