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

BACKGROUND

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

OBJECTIVES

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

METHODS

A targeted literature review was conducted to understand and identify AD-related disease sequelae and quality-of-life impacts relevant to patients with skin of colour 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 three clinical experts. Questionnaire content validity was explored during hybrid concept elicitation and cognitive debriefing interviews with 15 adult and adolescent patients with skin of colour who have moderate-to-severe AD.

RESULTS

Ten concept-focused articles, 3 websites, 17 labels, 1 U.S. Food and Drug Administration compendium and 1 clinical trial confirmed that xerosis and dyspigmentation are important AD-related disease sequelae. Patients with skin of colour [47% girls/women; mean (SD) age 33.3 (21.2) years] reported that the questionnaires were relevant to their AD experience in an appropriate recall timeframe and were readily understood, and that meaningful responses were easy to select. The final X-AD consisted of one 11-point numerical 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. This 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.