Development and preliminary validation of the patient‐reported Chronic Itch Burden Scale assessing health‐related quality of life in chronic pruritus. (1st September 2021)

• Record Type: Journal Article
• Authors: Theunis, J.; Nordon, C.; Falissard, B.; Orri, M.; Mengeaud, V.; Misery, L.
• Is Part Of: British journal of dermatology. Volume 186:Number 1(2022)
• Page Start: 86
• Page End: 95
• Publication Date: 2021-09-01
• Subjects: Dermatology -- Periodicals; Skin -- Diseases -- Periodicals; 616.5
• DOI: 10.1111/bjd.20582
• Languages: English
• ISSNs: 0007-0963

Abstract

Summary: Background: Chronic pruritus (CP) significantly affects patients' health‐related quality of life (HRQoL). Very few self‐reported HRQoL questionnaires exploring CP have been developed according to international guidelines, thus limiting their use in preauthorization trials. Objectives: To develop a self‐reported HRQoL questionnaire in patients with CP owing to psoriasis, atopic dermatitis, seborrhoeic dermatitis of the scalp or idiopathic dermatitis, and to explore the preliminary psychometric properties of the questionnaire. Methods: The study was performed in France. A conceptual framework was developed based on a structured literature review and expert insight, and was improved using three focus groups involving 19 participants. A 50‐item questionnaire was created and tested with 21 participants using cognitive debriefings; 11 items were removed. A cross‐sectional study including 251 participants was performed to explore the preliminary psychometric properties of the 39‐item questionnaire. Dimensionality was explored using principal component analysis. Cronbach's alpha and correlation coefficients (interitem, item‐total score and item‐dimension score) were measured. The number of items was reduced through expert consensus. Results: In the 39‐item version, three main dimensions were identified (Cronbach's alpha = 0·94) and all correlation coefficients were > 0·34. Upon review, 13 items were deleted owing to poor quality and six items were deleted by the team, generating a 20‐item version. The questionnaire's factorial structure was best reflected with a two‐dimension solution, i.e. (i) social and emotional repercussions and (ii) relation to others, fear of judgement. Conclusions: The Chronic Itch Burden Scale patient‐reported questionnaire explores broad aspects of HRQoL that are relevant for patients with various skin diseases. Its good cross‐sectional validity makes it useful for trials and practitioners. Abstract : What is already known about this topic? In order to be used in preauthorization trials, health‐related quality‐of‐life (HRQoL) questionnaires should be developed and validated according to international guidelines. What does this study add? A HRQoL questionnaire was developed in French, following guidelines, for patients with chronic pruritus secondary to psoriasis, atopic dermatitis, seborrhoeic dermatitis of the scalp or idiopathic dermatitis. The 20‐item version of the questionnaire revealed two underlying dimensions and showed good internal validity. What are the clinical implications of this work? The Chronic Itch Burden Scale is a 20‐item questionnaire developed using a robust, state‐of‐the‐art methodology and following the American and European guidelines for the development of patient‐reported outcome questionnaires; this involved a step‐by‐step process including qualitative and quantitative methods. Focus groups were insightful, as patients exhibited a tendency to attribute thoughts to others in relation to their itching behaviour (e.g. being seen as dirty) or scratching response (e.g. visible scars), thus leading to social avoidance impacting their social (and sexual) life. Moreover, negative illness cognitions were important to patients. Helplessness and resignation were highlighted as frequent cognitions that impacted patients' emotional life. Linked Comment: M. Gabes. Br J Dermatol 2022; 186 :10–11 .