1. Department of Paediatric Pulmonology and Allergology; Wilhelmina Children's Hospital; University Medical Centre Utrecht; Utrecht the Netherlands
2. Princess Amalia Children's Center; Isala Hospital; Zwolle the Netherlands
3. Unit of Psychology; Leiden University Medical Center; Leiden the Netherlands
4. UMCG Postgraduate School of Medicine; University Medical Center; University of Groningen; Groningen the Netherlands