1. Pediatric Surgical Centers of Amsterdam, Emma Children's Hospital Academic Medical Centre/VU Medical Center, Amsterdam, Netherlands
2. Division of Medical Psychology, University of Amsterdam, Amsterdam, Netherlands
3. Department of Pediatric Surgery, University Hospital of Maastricht, Maastricht, Netherlands
4. Department of Pediatric Surgery, University Hospital of Groningen, Groningen, Netherlands
5. Department of Pediatric Surgery, University Hospital of Rotterdam, Rotterdam, Netherlands
6. Department of Pediatric Surgery, University Hospital of Nijmegen, Nijmegen, Netherlands
7. Department of Pediatric Surgery, University Hospital of Utrecht, Utrecht, Netherlands
8. Patient Society of Anorectal Malformations, Nijverdal, Netherlands
9. Patient Society of Hirschsprung's Disease, Hilversum, Netherlands