Background
Epidermolysis bullosa (EB) is a rare, genetically and clinically heterogenous group of skin fragility disorders. No cure is available yet, but many novel and repurposed treatments are underway. For adequate evaluation and comparison of clinical studies in EB, well-defined and consistent consensus-endorsed outcomes and outcome measurement instruments are necessary.
Objectives
To identify previously reported outcomes in EB clinical research, group them in outcome domains and areas, and summarise respective outcome measurement instruments.
Methods
A systematic literature search was performed in the databases MEDLINE, Embase, Scopus, Cochrane CENTRAL, CINAHL, PsycINFO and trial registries covering the period between January 1991 and September 2021. Studies were included if they evaluated a treatment in a minimum of three EB patients. Two reviewers independently performed the study selection and data extraction. All identified outcomes and their respective instruments were mapped into overarching outcome domains. The outcome domains were stratified according to subgroups of EB type, age group, intervention, decade, and phase of clinical trial.
Results
The included studies (n?=?207) covered a range of study designs and geographical settings. A total of 1,280 outcomes were extracted verbatim and inductively mapped into 80 outcome domains and 14 outcome areas. We found a steady increase in number of published clinical trials and outcomes reported over the past 30 years. The included studies mainly focused on recessive dystrophic EB (43%). Wound healing was reported most frequently across all studies and referred to as a primary outcome in 31% of trials. Great heterogeneity of reported outcomes was observed within all stratified subgroups. Moreover, a diverse range of outcome measurement instruments (n?=?200) was identified.
Conclusions
We demonstrate substantial heterogeneity in reported outcomes and outcome measurement instruments in EB clinical research over the past 30 years. This review is the first step towards harmonisation of outcomes in EB, which is crucial to expedite clinical translation of novel treatments for EB patients.
Eva W H Korte, Tobias Welponer, Jan Kottner, Sjoukje van der Werf, Peter C van den Akker, Barbara Horváth, Dimitra Kiritsi, Martin Laimer, Anna M G Pasmooij, Verena Wally, Maria C Bolling
Disease Category: Genetic disorders, Skin
Disease Name: Epidermolysis bullosa
Age Range: Unknown
Sex:
Nature of Intervention:
- Systematic review of outcomes measured in trials