Revised Cutaneous Lupus Erythematosus Disease Area and Severity Index (RCLASI): a modified outcome instrument for cutaneous lupus erythematosus

Summary Background In 2005, a scoring system (CLASI, Cutaneous Lupus Erythematosus Disease Area and Severity Index) was developed for patients with cutaneous lupus erythematosus (CLE) to assess disease ‘activity’ and ‘damage’. However, the CLASI does not give an accurate assessment of the severity in all disease subtypes.

Objectives The main objective of this study was to analyse critically the included parameters of the CLASI and to revise the activity and damage score taking into account various clinical features of the different subtypes of CLE. The revised CLASI (RCLASI) was also validated for use in clinical trials.

Patients and methods A RCLASI was designed with regard to the anatomical region (i.e. face, chest, arms) and morphological aspects (i.e. erythema, scaling/hyperkeratosis, oedema/infiltration, scarring/atrophy) of skin lesions and evaluated by nine dermatologists who scored 12 patients with different subtypes of CLE to estimate inter- and intrarater reliability.

Results Reliability studies demonstrated an intraclass correlation coefficient (ICC) for an inter-rater reliability of 0·89 for the activity score [95% confidence interval (CI) 0·79–0·96] and of 0·79 for the damage score (95% CI 0·62–0·92). The ICC for intrarater reliability for the activity score was 0·92 (95% CI 0·89–0·95) and the ICC for the damage score was 0·95 (95% CI 0·92–0·98).

Conclusions In the present study, a RCLASI was developed by experts, and reliability studies supported the validity and applicability of the revised scoring instrument for CLE. Thus, the RCLASI is a valuable instrument in multicentre studies and for the clinical evaluation of activity and damage in different disease subtypes.