Christophersen, J; Menne, T; Tanghoj, P; Andersen, KE; Brandrup, F; Kaaber, K; Osmundsen, PE; Thestrup-Pedersen, K; Veien, NK
The influence of individual factors such as sex, age, atopy and presence of diseased skin, on clinical patch test results was evaluated, and a statistical model for standardization of the presentation of patch test results was proposed. The study was based on data from consecutive patients patch tested by the Danish Contact Dermatitis Group in seven different centers in Denmark during a 6 month period. The study population included 2166 patients. Nickel (7440020), fragrance mix, cobalt (7440484), chromate, balsam-of-Peru (8007009), carba mix, colophony, and formaldehyde (50000) were most often found positive. For the eight test allergens most often found positive one or more individual factors were of significance for the risk of being sensitized, except for chromate and formaldehyde. The authors conclude that an unequal frequency of patch test positive results is to be expected among groups of patients who differ with respect to individual variables. Patch test results can be compared only after stratification of the material or by multivariate analysis. Data analyzed in this way can be used to evaluate whether the frequency of a certain sensitivity rises or declines in the future, provided that the selection of patients for dermatological intervention and testing is fairly constant.