Assessing the dynamic changes in vitiligo: reliability and validity of the Vitiligo Disease Activity Score (VDAS) and Vitiligo Disease Improvement Score (VDIS)

Abstract

Background The assessment of the individual evolution of vitiligo is important for therapeutic decision making in daily practice. A fast, simple and validated physician-reported score to assess clinical changes in depigmentation over time in separate parts (activity and improvement) is currently missing.Objective The main objective of the study was to develop and validate the Vitiligo Disease Activity Score (VDAS) and Vitiligo Disease Improvement Score (VDIS).Methods The Vitiligo Disease Activity Score (VDAS) and Vitiligo Disease Improvement Score (VDIS) were evaluated based on a photo set of 66 patients with two different time points. In the first (short) version, only the number of changing body regions was counted based on 15 predefined areas (VDAS 15 and VDIS 15 ), while in the second (extensive) version the degree of worsening or improvement from +4 to À4 for each body area was added for a more detailed assessment (VDAS 60 and VDIS 60 ). Content and construct validity were tested. In addition inter-, intrarater reliability and feasibility were evaluated by 7 (test) and 5 (retest) physicians.Results Evidence for content and construct validity was provided. Overall, VDAS 15 , VDIS 15 , VDAS 60 and VDIS 60 demonstrated good to excellent inter-rater reliability [intraclass correlation (ICC): VDAS: range = 0.797-0.900; VDIS: range = 0.726-0.798]. The intrarater reliability ICCs were 0.865 and 0.781 for the VDAS 15 and VDIS 15 , respectively. Similar results were obtained for the VDAS 60 and VDIS 60 (ICC = 0.913 and 0.800, respectively). Completion time was short (median: 122 s/patient (first round); 95 s/patient (second round)].Limitations Single tertiary centre mainly of skin phototype 2 to 3. ConclusionThe VDAS and VDIS appear to be valid, reliable and feasible instruments to score the evolution of vitiligo lesions. This accommodates the current urgent need for a simple, standardized and practical assessment of vitiligo activity and improvement over time.

Clinician‐reported outcome measures for the assessment of vitiligo: A scoping review

“…For a long period of time, reliable, valid, and feasible ClinROMs to assess and quantify disease activity in vitiligo were lacking. Based on this need, several vitiligo disease activity tools were introduced and are described below 5,7,12–14,18,21–23 …”

Stability: Concept, relevance, inducing and maintaining it

“…4. Vitiligo Disease Activity score (VDAS) 33 : This is a subjective scoring system but it depends on patient recall and is subject to recall bias. A recent study found the VDAS and VDIS to be valid, reliable, and feasible instruments to score the evolution of vitiligo lesions.…”

Biomarkers and clinical indicators of disease activity in vitiligo

“…In clinical practice, disease activity is usually based on dynamic changes over time, potentially assisted by standardized scoring systems (e.g., VDAS and VDIS). 8 However, clinical visible signs can serve as a user-friendly, noninvasive marker for assessing disease activity in vitiligo at one specific time point. 23 A systematic review investigated the link between visible skin signs and disease activity, based on 46 articles.…”

“…Recently, the Vitiligo Disease Improvement Score (VDIS) and Vitiligo Disease Activity Score (VDAS) are developed and allow the physician to evaluate the improvement (VDIS) and worsening (VDAS) of the vitiligo, based on two specific moments while maintaining location-specific information. 8 A previously published protocol can guide the physician and researcher in taking standardized photographs. 9 At present, different new therapies are under investigation, based on targeting immune response regulatory pathways such as Janus kinase (JAK) inhibitors, 10 stressing the need for a valid marker for disease activity.…”