[1] Northwestern Univ, Dept Dermatol, Feinberg Sch Med, Chicago, IL 60611 USA
[2] Univ Calif San Francisco, Dept Dermatol, San Francisco, CA 94143 USA
[3] Northwestern Univ, Dept Prevent Med, Feinberg Sch Med, Chicago, IL 60611 USA
[4] Northwestern Univ, Dept Med Social Sci, Feinberg Sch Med, Chicago, IL 60611 USA