Patch Testing and Contact Allergen Avoidance in Patients With Lichen Planopilaris and/or Frontal Fibrosing Alopecia: A Cohort Study

J Am Acad Dermatol. 2020 Jan 19;S0190-9622(20)30077-3. doi: 10.1016/j.jaad.2020.01.026. Online ahead of print.