1. Department of Pediatrics, Division of Oncology-Hematology, VU University Medical Center Amsterdam, Amsterdam, the Netherlands (RRLVL, GJLK)
2. Department of Pediatrics, VU University Medical Center Amsterdam, Amsterdam, the Netherlands (AK, RJBJG)
3. Department of Pediatric Psychology & Social Work, University Medical Center Utrecht, Utrecht, the Netherlands (JH)
4. VU University Library Amsterdam, Amsterdam, the Netherlands (JCFK)