Validation of self-testing as a method to estimate the prevalence of nickel allergy

• Background: Valid epidemiological tools are required for surveillance of the prevalence of contact allergy. Population based studies including patch testing is the most reliable method, but implies heavy expenses and logistical problems. Clinical data are not representative for the general population and questionnaires concerning contact allergy have a low validity. Self-testing might be a useful method but it has to be validated and evaluated.Objectives: To investigate the validity of self-patch testing for nickel allergy. Methods: Patients from three dermatology clinics were included consecutively when referred to patch testing. In total, 191 patients participated and they were provided with a self-test package including written instructions. The self-test was applied on the arm by the patient, on the same day as the patch test was applied on the back, in the clinic. The patient evaluated the self-test before the patch test reading at the clinic.Results: Patch test at dermatology clinic (‘gold standard’) gave 46/191 (24%) nickel-positive individuals. The sensitivity of the self-test was 72% (95% CI 57–84), the specificity was 91% (95% CI 85–95) and the proportion of agreement was 86% (95% CI 81–91).Conclusions: The validity of self-testing for nickel allergy was adequate in the studied population. To determine whether self-testing is a useful tool for measuring the prevalence of nickel allergy in the general population further studies will be needed.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Dermatologi och venereologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Dermatology and Venereal Diseases (hsv//eng)

Nyckelord

contact allergy

epidemiology

patch test

self-test

sensitivity

specificity

MEDICINE

MEDICIN

Dermatology and venerology

Dermatologi och venerologi

Medicine

Medicin

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)