Four-week urticaria activity score-7 as a useful patient-reported outcome to assess chronic spontaneous urticaria: A multicentre study evaluation of adherence and patients’ perspective

Chronic spontaneous urticaria (CSU) is a condition characterized by the recurrence of itchy wheals without any specific trigger for longer than 6 weeks (1). In CSU the wheals fluctuate throughout the day. Therefore, measurement of the activity of the disease and of the effectiveness of treatments is by means of patient-reported outcome (PRO) instruments, such as the Urticaria Activity Score (UAS) (2). The UAS is a quantitative daily diary that includes a once-a-day (3) or twice-a-day (4) self-evaluation score. It is used for both clinical practice and trials to assess disease activity and treatment efficacy (1). Due to the chronicity and remarkable instability of CSU, daily UAS scores are summed over one week to create the UAS7 (3). However, there is a lack of information on adherence to the instrument and the precision with which it is completed. The aim of this study was to evaluate adherence to the once-a-day UAS7 in real life, through an observational, descriptive, multicentre study on consecutive patients with CSU aged ≥18 years.