A new self‐reported measure of disease severity of scalp hair loss in alopecia areata
Authors: F. Rencz
Journal: British Journal of Dermatology (2020)

Linked Article: Wyrwich et al. Br J Dermatol 2020; 183:1065–1072. Alopecia areata (AA) is a common autoimmune disease of the hair follicles that causes nonscarring hair loss.1, 2 It most frequently affects the scalp; however, it may involve any hair-bearing site on the body. The pivotal role of hair in a person's appearance and expressing one's identity is well known. Patients with AA face the psychological impact of losing their hair, which may lead to lower self-esteem, higher level of anxiety and depression and poorer health-related quality of life (HRQoL).3-5 Physicians and patients often have different perceptions about the disease, expectations about treatments and preferences for outcomes. In recent years, understanding the subjectivity of patients’ perceptions, emotions and needs, has led to the development of a growing number of AA-specific patient-reported outcome measures (PROMs). Some of these measures, such as the Alopecia Areata Symptom Impact Scale6 and the Alopecia Areata Quality of Life Index (AA-QLI)7 ask patients both about their objective symptoms and HRQoL, whereas other instruments, such as the Alopecia Areata Quality of Life,8 specifically address various domains of disease-specific HRQoL, for example, restriction of activities, concealment and adaptation. These AA-specific PROMs are typically longer, consisting of seven to 21 questionnaire items. In this issue of BJD, Wyrwich et al. reported on the development a new, AA-specific PROM to assess disease severity of scalp hair loss.9 The Scalp Hair Assessment PRO™ has been developed and refined using cognitive interviewing with 45 patients with AA in the USA. Concept elicitation revealed that among the several characteristics describing the hair loss or regrowth (e.g. location, quantity and thickness), quantity was the most important factor for patients with AA. Building on this, the authors developed an easy-to-use single-item instrument that allows patients to rate their hair loss in terms of quantity. The percentage of scalp surface with missing hair is measured on a five-point scale (0%, no missing hair; 1–20%, limited; 21–49%, moderate; 50–94%, large; 95–100%, nearly all or all). Patients with AA participating in the cognitive interviews agreed that having ≤ 20% missing hair indicated a treatment success on this scale. Advantages of the new PROM include simplicity, low patient burden and comparability with the Alopecia Areata Investigator Global Assessment (AA-IGA) measure.10 On the other hand, its brevity may also be viewed as a weakness because other symptoms possibly relevant for patients with AA, such as itch, irritation and pain of the scalp, body hair loss or nail involvement, are not covered by the single-item instrument. The Scalp Hair Assessment PRO™ seems to be a content-valid and practical PROM for patients with AA that can be used for monitoring treatment effects and hair loss or regrowth in various clinical and research settings, such as patient diaries and clinical trials. Nevertheless, in spite of the positive evidence of content validity, its psychometric performance in various patient populations, including construct validity, test–retest reliability, responsiveness and agreement with AA-IGA, requires further evaluation.