C.Y. Zhao , , A.Q.T. Tran , J.P. Lazo-Dizon , J. Kim , , B.S. Daniel , , S.S. Venugopal , L.M. Rhodes , M.G. Law , D.F. Murrell
Background: There are multiple outcome measures for
the clinical severity of atopic dermatitis (AD), but a need to
compare the reliability of these measures.
Aims:
1. Compare the inter-rater and intra-rater reliability of the
objective Scoring Atopic Dermatitis (oSCORAD), Eczema
Area and Severity Index (EASI), Six Area, Six Sign Atopic
Dermatitis (SASSAD) and Three Item Severity index
(TIS)
2. Correlate these outcome measures to QoL instruments:
Patient-Orientated Eczema Measurement, Dermatology
Life Quality Index and SkinDex-29.
Methods: Twelve AD patients were attended a scoring
session by 5 fully trained clinicians, using the above 4
outcome measures. Statistics were performed using SPSS.
Results: Regarding inter-rater reliability, EASI and SASSAD
showed good reliabilities with 0.730 (95% CI = 0.500–0.900)
and 0.680 (95% CI = 0.440–0.880), respectively. However
inter-rater ICCs were only fair for TIS and oSCORAD with
0.497 (95% CI = 0.233–0.785) and 0.498 (95% CI = 0.234–
0.785), respectively. Regarding intra-rater reliability, EASI
and TIS showed excellent ICCs of 0.886 (95% CI: 0.744–
0.952) and 0.820 (0.614–0.923), respectively, while SASSAD
showed good reliability with ICC of 0.720 (95% CI = 0.424–
0.878). However intra-rater ICCs were only fair for oSCORAD
with 0.446 (95%CI = 0.037–0.730). Regarding correlation
with QoL instruments, only SASSAD demonstrated moderate
correlation with SkinDex-29, ρ = 0.611 (p = 0.035).
Conclusions: Consistent wit the latest Harmonising Core
Outcome Measures for Atopic Dermatitis Clinical Trials
initiative consensus,
EASI demonstrated the highest interrater
and intra-rater reliability, supporting it as the optimal
measure. Our study elucidated the need for an outcome
measure which eliminates surface area error and independently
assesses activity and damage.