Statistical and comparative study of 4600 patients tested in Barcelona (1973-1977).

The authors show the results obtained during the 5-year period 1973-1977 in 4600 patch tested patients in the Allergy Department of Barcelona University. The results obtained with the most common allergens (nickel sulfate, potassium dichromate, para compounds, cobalt and rubber) are studied separately. The results of testing with the allergens with a low incidence of positives are also shown. The results are compared with those published by the NACDG on 1200 patients and by Brun in Geneva on 1000 patients; 5.02% of the tested patients showed sensitization to benzidine.