Validation of the Vitiligo Noticeability Scale: a patient‐reported outcome measure of vitiligo treatment success3. (14th December 2015)

• Record Type: Journal Article
• Authors: Batchelor, J.M.; Tan, W.; Tour, S.; Yong, A.; Montgomery, A.A.; Thomas, K.S.
• Is Part Of: British journal of dermatology. Volume 174:Number 2(2016)
• Page Start: 386
• Page End: 394
• Publication Date: 2015-12-14
• Subjects: Dermatology -- Periodicals; Skin -- Diseases -- Periodicals; 616.5
• DOI: 10.1111/bjd.14208
• Languages: English
• ISSNs: 0007-0963

Abstract

Summary: Background: Patient‐reported outcome measures are rarely used in vitiligo trials. The Vitiligo Noticeability Scale (VNS) is a new patient‐reported outcome measure assessing how 'noticeable' vitiligo patches are after treatment. The noticeability of vitiligo after treatment is an important indicator of treatment success from the patient's perspective. Objectives: To evaluate the construct validity, acceptability and interpretability of the VNS. Methods: Clinicians ( n = 33) and patients with vitiligo ( n = 101) examined 39 image pairs, each depicting a vitiligo lesion pre‐ and post‐treatment. Using an online questionnaire, respondents gave a global assessment of treatment success and a VNS score for treatment response. Clinicians also estimated percentage repigmentation of lesions (< 25%; 25–50%; 51–75%; > 75%). Treatment success was defined as 'yes' on global assessment, a VNS score of 4 or 5, and > 75% repigmentation. Agreement between respondents and the different scales was assessed using kappa (κ) statistics. Results: Vitiligo Noticeability Scale scores were associated with both patient‐ and clinician‐reported global treatment success (κ = 0·54 and κ = 0·47, respectively). Percentage repigmentation showed a weaker association with patient‐ and clinician‐reported global treatment success (κ = 0·39 and κ = 0·29, respectively). VNS scores of 4 or 5 can be interpreted as representing treatment success. Images depicting post‐treatment hyperpigmentation were less likely to be rated as successful. Conclusions: The VNS is a valid patient‐reported measure of vitiligo treatment success. Further validation of the VNS is required, using larger sets of clinical pre‐ and post‐treatment images, affecting a wider range of anatomical sites. Abstract : What's already known about this topic? The lack of standardized outcome measures makes comparison of vitiligo treatment efficacy difficult. Patient‐reported outcome measures are rarely used in vitiligo trials. Patient‐reported outcome measures assessing vitiligo treatment success from the patient's perspective have yet to be developed. The Vitiligo Noticeability Scale (VNS) is a new patient‐reported outcome measure of treatment response, which has been shown to have face validity. What does this study add? The VNS has good construct validity, acceptability and interpretability, supporting its inclusion as a patient‐reported measure of the cosmetic acceptability of treatment response in vitiligo trials. The VNS is a better and more consistent indicator of global treatment success than percentage repigmentation. VNS scores of 4 or 5 can be interpreted as representing treatment success. Further validation of the VNS is required. Plain language summary available online