Standardizing the assessment of clinical signs of atopic eczema

Atopic eczema (AE, syn. atopic dermatitis) is a major medical condition that causes substantial burden to patients, their families, and society. Various different interventions exist, many of which have been assessed in randomized controlled trials (RCTs). However, there is a lack of core outcome sets for atopic eczema (AE) which is a major obstacle for advancing evidence-based treatment.  There are several different instruments identified to assess clinical signs of AE and the global Harmonizing Outcome Measures for Eczema (HOME) initiative has already defined clinical signs, symptoms, quality of life, and long-term control of flares as core outcome domains for AE-trials. To resolve the current lack of standardization of the assessment of clinical signs of AE, the HOME initiative followed a structured process of systematic reviews and international consensus sessions to identify one core outcome measurement instrument to assess clinical signs in all future AE-trials (J Allergy Clin Immunol 2014; 134(4): 800-807).

The authors determined that from 16 different instruments identified to assess clinical signs of AE, only the Eczema Area and Severity Index (EASI) and the objective Scoring Atopic Dermatitis Index (objective SCORAD) were identified as sufficiently tested for inclusion in the core outcome set. The EASI has adequate validity, responsiveness, internal consistency, and intra-observer reliability. The objective SCORAD has adequate validity, responsiveness, and inter-observer reliability, but unclear intra-observer reliability to measure clinical signs of AE. In an international consensus study, patients, physicians, nurses, methodologists, and pharmaceutical industry representatives agreed that EASI is the preferred core instrument to measure clinical signs in all future AE-trials. The EASI was chosen as the core outcome measure for clinical trials because (1) it only includes the 4 essential signs, (2) assesses the severity of AE signs at multiple body sites, rather than at a single representative site for each sign, and (3) gives the extent of AE lesions sufficient weighting.

The HOME initiative recommends that all investigators, pharmaceutical industry, and regulatory authorities observe this consensus and include the EASI in all future atopic eczema trials to enable improved evidence-based decision making and scientific communication in the future. This does not preclude the use of other scales in trials (such as SCORAD) in addition to the core outcome measure. Better training materials for use of EASI are in preparation and will be freely available via the HOME website (www.homeforeczema.org). Furthermore, the process of standardization and selection of measurement instruments for the assessment of the other core outcome domains of AE, i.e. symptoms such as pruritus and sleeping problems, quality of life and long-term control of flares, is currently underway.