The cutaneous lupus erythematosus disease activity and severity index: Expansion for rheumatology and dermatology

Abstract
Objective To evaluate the validity of the Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) for use by rheumatologists via reliability testing, and to extend the validation for dermatologists. Methods Fourteen subjects with cutaneous lupus erythematosus (CLE; n = 10), a mimicker skin disease only (a cutaneous lesion that may appear clinically similar to CLE; n = 1), or both (n = 3) were rated with the CLASI by academic‐based dermatologists (n = 5) and rheumatologists (n = 5). Results The dermatology intraclass correlation coefficient (ICC) was 0.92 for activity and 0.82 for damage; for rheumatology the ICC was 0.83 for activity and 0.86 for damage. For intrarater reliability, the dermatology Spearman's rho was 0.94 for activity and 0.97 for damage; for rheumatology the Spearman's rho was 0.91 for activity and 0.99 for damage. Conclusion Our data confirm the reliability of the CLASI when used by dermatologists and support the CLASI as a reliable instrument for use by rheumatologists.