In 2015, an international Core Outcome Domain Set (CODS) for vitiligo randomised controlled trials (RCTs) was developed through systematic review, patient involvement, and international consensus. This represented a major milestone in vitiligo research by establishing a minimum set of essential and recommended outcome domains for clinical trials. Since then, numerous RCTs evaluating novel therapies have been published. However, an updated systematic review on outcomes used in RCTs demonstrated limited implementation of the existing CODS, with only 11 of 112 trials reporting all essential domains and none reporting both essential and recommended domains. Considerable heterogeneity in outcome domains and measurement instruments persists, while important patient-centred outcomes, including quality of life and cosmetic acceptability, remain under-reported. These findings highlight the need to update the existing CODS to ensure it remains relevant, comprehensive, and aligned with contemporary clinical practice and stakeholder priorities.
Objective: To update the existing international Core Outcome Domain Set for vitiligo randomised controlled trials, ensuring its continued relevance, inclusivity, and applicability to contemporary vitiligo research.
Methods: This study will follow a multi-stage mixed-methods design informed by COMET and COS-STAD recommendations and aligned with the original CODS methodology to ensure continuity and comparability. The update will build on a recently completed systematic review evaluating outcome reporting and implementation of the existing CODS in vitiligo RCTs. Patient and public involvement workshops will explore the relevance, clarity, and completeness of the current domains, with particular emphasis on representation across diverse ethnic backgrounds, skin phototypes, and cultural settings. An international multidisciplinary stakeholder panel, including dermatologists, specialist nurses, psychologists, patients, clinical trialists, systematic reviewers, and patient organisation representatives, will participate in a two-round modified electronic Delphi process. Participants will rate the importance of retaining, refining, or updating each existing domain using a 9-point Likert scale. Consensus will be predefined as =70% of participants scoring a domain as critical (7–9) and =15% scoring it as not important (1–3). An international steering committee will oversee the process and ensure consistency with the original CODS framework.
Discussion: This study represents an evidence-informed update of the internationally endorsed vitiligo CODS rather than the development of a new core outcome set. By integrating contemporary evidence with renewed international stakeholder and patient engagement, the updated CODS aims to improve standardisation of outcome reporting, reduce heterogeneity across trials, and ensure that future vitiligo research consistently measures outcomes that are clinically meaningful and important to patients. The updated CODS is expected to facilitate evidence synthesis, improve trial comparability, and support clinical decision-making, guideline development, and regulatory evaluation of emerging vitiligo therapies.
Vitiligo International Patient Organisation Committee (VIPOC – worldwide alliance of vitiligo patients’ organisations)
Vitiligo Society UK (VS)
Vitiligo Support Group (VSG; UK)
Global Vitiligo Foundation (GVF; United States)
Association Française du Vitiligo (AFV; France).
University of Keele, UK
Université Paris-Est (UPE), France
Global Vitiligo Atlas
Disease Category: Skin
Disease Name: Vitiligo
Age Range: 0 - 100
Sex: Either
Nature of Intervention: Any
- Charities
- Clinical experts
- Consumers (caregivers)
- Consumers (patients)
- Methodologists
- Patient/ support group representatives
- Researchers
- Statisticians
- COS for clinical trials or clinical research
- Delphi process
- Focus group(s)
- Interview
This study will follow a multi-stage mixed-methods design informed by COMET and COS-STAD recommendations and aligned with the original CODS methodology to ensure continuity and comparability. The update will build on a recently completed systematic review evaluating outcome reporting and implementation of the existing CODS in vitiligo RCTs. Patient and public involvement workshops will explore the relevance, clarity, and completeness of the current domains, with particular emphasis on representation across diverse ethnic backgrounds, skin phototypes, and cultural settings. An international multidisciplinary stakeholder panel, including dermatologists, specialist nurses, psychologists, patients, clinical trialists, systematic reviewers, and patient organisation representatives, will participate in a two-round modified electronic Delphi process. Participants will rate the importance of retaining, refining, or updating each existing domain using a 9-point Likert scale. Consensus will be predefined as =70% of participants scoring a domain as critical (7–9) and =15% scoring it as not important (1–3). An international steering committee will oversee the process and ensure consistency with the original CODS framework.