Development of novel patient-reported outcome instruments to assess atopic dermatitis-associated dyspigmentation and xerosis in patients with skin of colour.

Abstract

Background: The prevalence and burden of atopic dermatitis (AD) are disproportionately high in individuals with skin of colour (SOC). Previous research shows that risk for xerosis and/or dyspigmentation is heightened in this population and may be more bothersome. However, there are no patient-reported instruments developed specifically for these disease sequelae in patients with SOC.

Objectives: To develop and perform content validation of patient-reported outcome (PRO) questionnaires to assess AD-related xerosis and dyspigmentation in patients with SOC.

Methods: A targeted literature review was conducted to understand and identify AD-related disease sequelae and quality-of-life impacts relevant to patients with SOC and any instruments used to assess AD in the target population. Two draft PRO questionnaires assessing xerosis (X-AD) and dyspigmentation (D-AD) were developed and refined following advice meetings with clinical experts (N = 3). Questionnaire content validity was explored during hybrid concept elicitation (CE) and cognitive-debriefing (CD) interviews with adult and adolescent patients with SOC who have moderate-to-severe AD (N = 15).

Results: Ten concept-focused articles, three websites, 17 labels, one United States Food and Drug Administration compendium and one clinical trial confirmed xerosis and dyspigmentation were important AD-related disease sequelae. Patients with SOC (46.7% female; age range 12.2-76.1 years) reported that each questionnaire was relevant to their AD experience in an appropriate recall timeframe, were readily understood and meaningful responses were easy to select. The final X-AD consisted of one 11-point numeric rating scale (NRS) assessing xerosis severity and two items assessing the level of bother associated with xerosis appearance and feeling over the past week (0-4 verbal rating scale). The final D-AD consisted of two 11-point NRS items assessing dyspigmentation severity and two items assessing the level of bother associated with how dyspigmentation looked over the past week.

Conclusions: The X-AD/D-AD questionnaires were well understood and effective in capturing the experiences of xerosis and dyspigmentation in the target population in an appropriate and comprehensive way. The study supports the initial development of the questionnaires in accordance with regulatory guidelines and best practices, however psychometric validation is required to evaluate the properties of each questionnaire and develop score interpretation guidelines.