1. Pediatric Pain Service; Department of Anesthesiology; The Juliane Marie Centre; Copenhagen University Hospital Rigshospitalet; Copenhagen Denmark
2. Department of Drug Design and Pharmacology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
3. Department of Pediatrics; Copenhagen University Hospital Herlev; Copenhagen Denmark
4. Department of Pain Medicine, Palliative Care & Integrative Medicine; Children's Hospitals and Clinics of Minnesota; Minneapolis MN USA
5. Department of Pediatrics; University of Minnesota Medical School; Minneapolis MN USA