Measurement of the severity of rosacea.

Abstract

There are no standardized measures for the severity of rosacea. To determine what clinical signs correlate best with global severity of rosacea, and to examine inter-rater reliability. Methods Four clinicians each made 82 assessments of rosacea patients. Each assessment used 60 0-to-10 Likert-like scales for the signs of rosacea. Subjects also assessed the severity of their rosacea. The clinicians' assessment of global severity correlated strongly with erythema, especially on the cheeks. Subjects' assessment of global severity correlated more strongly with papules/pustules. Different methods of assessing severity--estimation of area involved, intensity, or lesion counts--did not produce significantly different results. Inter-rater reliability was low on 11-point (0-10) scales, but improved when scales were collapsed to 5 or 4 points. Clinicians and patients assess severity of rosacea differently, with clinicians focusing on erythema and patients focusing on papules/pustules. New instruments for assessing severity must address inter-rater reliability.