What are the best outcome measurements for atopic eczema? A systematic review

Background

Valid and reliable outcome measurements are a prerequisite for evidence-based practice. The comparative validity and reliability of outcome measurements for assessing atopic eczema (AE) severity is unclear.

Objective

We sought to assess the validity, reliability, sensitivity to change, and ease of use of outcome measurements for AE. We also sought to give recommendations on which outcomes to use in clinical research and for clinical monitoring.

Methods

We performed a systematic review and survey of clinical experts and patients.

Results

Twenty published outcome measurements were identified. There is evidence of adequate construct validity for 3 measurements (Severity Scoring of Atopic Dermatitis index [SCORAD], Eczema Area and Severity Index [EASI], and Three Item Severity Score), adequate internal consistency of 1 scale (Patient-oriented Eczema Measure [POEM]), adequate interobserver reliability of 5 measurements (Basic Clinical Scoring System; Nottingham Eczema Severity Score; Objective Severity Assessment of Atopic Dermatitis; Six Area, Six Sign Atopic Dermatitis severity score; and SCORAD), adequate test-retest reliability of 1 scale (POEM), and adequate sensitivity to change of 3 measurements (EASI, SCORAD, and Investigators' Global Atopic Dermatitis Assessment). Most outcome measurements have adequate content validity, as assessed by patients and experts. Data on the time to perform the assessment was identified for 8 outcome measurements. Only SCORAD, EASI, and POEM have been tested sufficiently and performed adequately.

Conclusion

There are too many published outcome measures for AE. Most have not been tested properly or perform adequately when tested, and their continued use hampers scientific communication.

Clinical implications

Only SCORAD, EASI, and POEM currently perform adequately. These scales should be used in future studies.

Key words: Atopic eczema, clinical research, evidence-based medicine, outcome measurement, reliability, severity of illness index, validity

Abbreviations used: AE, Atopic eczema, EASI, Eczema Area and Severity Index, FSSS, Four Step Severity Score, IGA, Investigators' Global Assessment, IGADA, Investigators' Global Atopic Dermatitis Assessment, NESS, Nottingham Eczema Severity Score, OSAAD, Objective Severity Assessment of Atopic Dermatitis, POEM, Patient-oriented Eczema Measure, RCT, Randomized controlled trial, RL score, Rajka and Langeland score, SA-EASI, Self-administered Eczema Area and Severity Index, SASSAD, Six Area, Six Sign Atopic Dermatitis severity score, SCORAD, Severity Scoring of Atopic Dermatitis index, SIS, Skin Intensity Score, SSS, Simple Scoring System, TBSA, Six-area Total Body Severity Assessment, TISS, Three Item Severity Score, WAZ-S, Atopic dermatitis severity score (in Polish)