1. Utrecht University Institute for Risk Assessment Sciences (IRAS), Division of Environmental Epidemiology, , Utrecht, the Netherlands
2. National Institute for Public Health and the Environment (RIVM) Centre for Nutrition, Prevention and Health Services, , Utrecht, The Netherlands
3. University of Groningen Department of Pediatric Pulmonology and Pediatric Allergology, , University Medical Centre Groningen, Beatrix Children’s Hospital, Groningen, the Netherlands
4. University Medical Centre Groningen Research Institute of Asthma and COPD (GRIAC), University of Groningen, , Groningen, Groningen, the Netherlands
5. University Medical Centre Groningen Department of Epidemiology, University of Groningen, , Groningen, the Netherlands
6. University Medical Centre Utrecht Julius Centre for Health Sciences and Primary Care, , Utrecht, the Netherlands