SummaryBackground Itching is a profoundly distressing symptom for many patients with psoriasis, but it has not been rigorously studied using validated tools for this condition. Objectives This study investigated the psychometric properties of the Itch Numeric Rating Scale (Itch NRS), a single-item patient-reported outcome (PRO) measuring the worst itching severity due to psoriasis in the past 24 h. Methods Using disease-specific clinician-rated and PRO data from one phase II and three phase III randomized clinical studies of subjects with moderate-to-severe plaque psoriasis, the Itch NRS was evaluated for test-retest reliability, construct validity and responsiveness. A responder definition was explored using anchorand distribution-based methods. Results Test-retest reliability analyses supported the reproducibility of the measure (intraclass correlation coefficient range 0Á71-0Á74). To support the construct validity of the Itch NRS, large cross-sectional correlations with the Dermatology Life Quality Index (DLQI) Symptoms and Feelings domain (r ≥ 0Á60 at baseline and r ≥ 0Á80 at week 12) supported a priori hypotheses, while large correlations (r ≥ 0Á71) between changes in Itch NRS scores and changes in DLQI Symptoms and Feelings domain scores from baseline to week 12 established responsiveness. A 4-point change was optimal for demonstrating a level of clinically meaningful improvement in itch severity after 12 weeks of treatment, which corresponds with marked clinical improvements in plaque psoriasis. Conclusions The Itch NRS demonstrated sufficient reliability, validity and responsiveness, and appropriate interpretation standards for evaluating change over time in itch severity among patients with moderate-to-severe plaque psoriasis when validated using clinical trial data for this condition.

There may be no excess mortality among patients with CDAD, compared with patients without it, but the economic burden of CDAD is increasing. By 2004, CDAD-associated medical expenditures approached $1,000,000 per year at our institution alone.

Plaque psoriasis (PP) and psoriatic arthritis (PsA) are autoinflammatory chronic conditions associated with skin involvement. Pruritus, or itching, is a prevalent and bothersome symptom in patients with PP and is associated with reduced health-related quality of life. The Worst Itch Numeric Rating Scale (WI-NRS) has been developed as a simple, single item with which to assess the patient-reported severity of this symptom at its most intense during the previous 24-hour period. Qualitative research was undertaken to assess the content validity of the WI-NRS. Patients with moderate to severe PP and patients with PsA were recruited from clinical sites in the USA. The qualitative research entailed two-part interviews, which began with concept elicitation to gain understanding of patients' experiences of itching, followed by cognitive debriefing of the WI-NRS to assess the instrument's understandability, clarity, and degree of appropriateness from the patient's perspective. Twelve patients with PP and 22 with PsA participated in the study. Patients reported that itching was an important and relevant symptom of their psoriatic disease. The WI-NRS was reported to be complete and easy to understand; the recall period was considered appropriate, the response scale was familiar, and, overall, the instrument was found to be appropriate for assessing itching severity. Patient responses support the content validity of the WI-NRS. The psychometric properties of the tool will be evaluated in future studies.

Ixekizumab was superior to placebo for the treatment of moderate-to-severe GenPs with BSA ≥ 1%. The safety profile of ixekizumab was consistent with previous studies in moderate-to-severe plaque psoriasis.

The conceptual model illustrates the wide-reaching impact of SLE symptoms on a patient's HRQL, and the potential broad impact of a treatment that improves SLE symptoms.