Contact Dermatitis 2007: 57: 265–272 Printed in Singapore. All rights reserved # 2007 The Authors Journal compilation # 2007 Blackwell Munksgaard CONTACT DERMATITIS 10-year prevalence of contact allergy in the general population in Denmark estimated through the CE-DUR method JACOB PONTOPPIDAN THYSSEN 1 ,WOLFGANG UTER 2 ,AXEL SCHNUCH 3 ,ALLAN LINNEBERG 4 AND JEANNE DUUS JOHANSEN 1 1 National Allergy Research Centre, Department of Dermatology, Gentofte University Hospital, 1. 2820 Gentofte, Denmark, 2 Department of Medical Informatics, Biometry and Epidemiology, Friedrich Alexander University, Erlangen-Nu¨ rnberg, Germany, 3 Information Network of Departments of Dermatology, Institute at the Georg-August Universita¨t Go¨ ttingen, Go¨ ttingen, Germany, and 4 Research Centre for Prevention and Health, Glostrup University Hospital, Glostrup, Denmark The prevalence of contact allergy in the general population has traditionally been investigated through population-based epidemiological studies. A different approach is the combination of clin- ical epidemiological (CE) data and the World Health Organization-defined drug utilization research (DUR) method. The CE-DUR method was applied in Denmark to estimate the prevalence of contact allergy in the general population and compare it with the prevalence estimates from the Glostrup allergy studies. Contact allergy prevalence estimates ranging from very liberal (‘worst case’) to conservative (‘best case’) assumptions were based on patch test reading data in combination with an estimate of the number of persons eligible for patch testing each year based on sales data of the ‘standard series’. The estimated 10-year prevalence of contact allergy ranged between 7.3% and 12.9% for adult Danes older than 18 years. The 10-year prevalence of contact allergy measured by CE-DUR was slightly lower than previous prevalence estimates from the Glostrup allergy studies. This could probably be explained by a decrease in nickel allergy. The CE-DUR approach holds the potential of being an efficient and easy monitoring method of contact allergy prevalence. Key words: CE-DUR; contact allergy; contact dermatitis; DUR; fragrance mix; nickel; prevalence clinical epidemiology. # Blackwell Munksgaard, 2007. Accepted for publication 29 May 2007 The prevalence of contact allergy in the general population has previously been estimated by population-based epidemiological studies (1–6). Such large studies demand planning as well as resources and are therefore not applicable in all countries. Furthermore, they cannot be repeated frequently to monitor trends in contact allergy. The drug utilization research (DUR) was de- fined by the World Health Organization in 1977 as research addressing ‘the marketing, distribu- tion, prescription, and use of drugs in a society, with special emphasis on the resulting medical, social and economic consequences’ (7). Briefly, this method estimates the number of diseased persons in a population based on information about specific drug prescription and consumption (8, 9). In 2002, the DUR approach was used in combination with clinical epidemiological (CE) data to estimate the prevalence of contact allergy in Germany (10). The CE-DUR method is mainly based on the total annual patch test sales, which is justified as patch testing is uniquely used for the diagnosis of contact allergy as a cause of al- lergic contact dermatitis (ACD). The results of the study were largely in accordance with previous epidemiological studies but not directly compa- rable with prevalence estimates from Denmark because of different medical systems as well as the methods itself. The Glostrup allergy studies from 1990 to 1998 estimated the prevalence of contact allergy in a general population in Denmark (3, 5). The main objective of the present investigation was to apply the CE-DUR approach in Denmark to estimate the 10-year prevalence of contact allergy and compare it with prevalence outcomes from the Glostrup allergy studies. It is our hope that this will help determine the quality of the CE-DUR