The Alopecia Areata Consensus of Experts (ACE) study part II: Results of an international expert opinion on diagnosis and laboratory evaluation for alopecia areata.

Background: We previously reported the Alopecia Areata Consensus of Experts study, which presented results of an international expert opinion on treatments for alopecia areata.

Objective: To report the results of the Alopecia Areata Consensus of Experts international expert opinion on diagnosis and laboratory evaluation for alopecia areata.

Methods: Fifty hair experts from 5 continents were invited to participate in a 3-round Delphi process. Consensus threshold was set at greater than or equal to 66%.

Results: Of 148 questions, expert consensus was achieved in 82 (55%). Round 1 consensus was achieved in 10 of 148 questions (7%). Round 2 achieved consensus in 47 of 77 questions (61%). The final face-to-face achieved consensus in 25 of 32 questions (78%). Consensus was greatest for laboratory evaluation (12 of 14 questions [86%]), followed by diagnosis (11 of 14 questions [79%]) of alopecia areata. Overall, etiopathogenesis achieved the least category consensus (31 of 68 questions [46%]).

Limitations: The study had low representation from Africa, South America, and Asia.

Conclusion: There is expert consensus on aspects of epidemiology, etiopathogenesis, clinical features, diagnosis, laboratory evaluation, and prognostic indicators of alopecia areata. The study also highlights areas where future clinical research could be directed to address unresolved hypotheses in alopecia areata patient care.