Protocol for the development of a core domain set for hand eczema trials

Background Clinical hand eczema trials measure a variety of outcome domains to determine the success of interventions. This considerably limits the comparability and overall confidence in the study results, and thereby the strength of recommendations for clinical practice. Objectives The Hand Eczema Core Outcome Set (HECOS) initiative aims to develop a core outcome set (COS) for the standardized evaluation of interventions in future hand eczema trials and reviews. This COS will define the minimum that should be measured and reported in controlled and randomized-controlled trials of therapeutic hand eczema interventions. The objective of this protocol is to specify the methods to develop a core domain set. Methods In Phase 1, a list of candidate domains will be derived from a systematic literature review concerning previously measured outcomes in hand eczema trials, from qualitative patient interviews and from expert interviews. In Phase 2, a consensus study about core domains will be conducted by an online 3-round Delphi survey and a face-to-face meeting, applying predefined consensus criteria. HECOS involves hand eczema and methods experts as well as patients and further stakeholders with an interest in the initiative. Outlook When a set of core domains has been defined, HECOS is going to identify appropriate outcome measurement instruments in a development process that will be detailed in another protocol. The COS will considerably enhance the methodological quality, comparability and usefulness of hand eczema trials for clinical decision-making and the development of new therapeutic options for hand eczema, and also reduce the effort of planning, conducting, and reporting individual hand eczema studies, reviews and meta-analyses.