J Allergy Clin Immunol 2014 Mar 6;133(3):885-8. Epub 2013 Dec 6.
Department of Epidemiology, University of Groningen, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Groningen Research Institute for Asthma and COPD (GRIAC), University of Groningen, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands. Electronic address: