Validation of the Cholinergic Urticaria Activity Score (CholUAS).

BACKGROUND

In cholinergic urticaria (CholU), itchy wheal and flare-type skin reactions are triggered by sweat-inducing activities. The CholU activity score (CholUAS) is used to assess disease activity but has not yet been validated. The aim of the study was to validate the CholUAS, develop an English version, and provide instructions for scoring.

METHODS

Cognitive debriefing of CholUAS was performed. Patients with CholU (n = 75) used the CholUAS on 7 consecutive days, underwent provocation testing, completed additional anchor instrument questionnaires including global evaluation tools, and established quality of life instruments. A scoring protocol for the calculation of the weekly CholUAS, the CholUAS7, was developed. The CholUAS7 was tested for validity, reliability, and influencing factors. An English version of the CholUAS was developed.

RESULTS

The final CholUAS contains 3 questions that are used for scoring as well as 1 global question. The weekly CholUAS, CholUAS7, showed excellent test-retest reliability and good correlations with anchor instruments. Statistical analysis showed no significant influence of age or duration of disease on CholUAS7 results.

CONCLUSION

The validated CholUAS is ready for use in clinical trials and routine clinical practice.