1 University of Erlangen/Nürnberg, Department of Medical Informatics, Biometry and Epidemiology, Waldstr. 6, 91054 Erlangen, Germany. Electronic address: wolfgang.uter@fau.de.
2 National Allergy Research Centre, Dermatology and Allergy, Herlev- Gentofte Hospital, University of Copenhagen, Kildegårdsvej 28, 2900 Hellerup, Denmark. Electronic address: Jeanne.Duus.Johansen@regionh.dk.
3 Karolinska Institutet, Institute of Environmental Medicine, Box 210, 17177 Stockholm, Sweden. Electronic address: carola.liden@ki.se.
4 University of Strasbourg, CNRS, CHIMIE UMR 7177, F-67000 Strasbourg, France. Electronic address: jplepoit@unistra.fr.
5 St. John's Institute of Dermatology, St. Thomas' Hospital, London SE1 9RT, United Kingdom. Electronic address: ian.white@kcl.ac.uk.