1. Department of Clinical Pediatrics, University of Texas M. D. Anderson Cancer Center, Houston, Texas
2. Department of Preventive and Societal Medicine, University of Nebraska Medical Center, Omaha, Nebraska
3. University of Wales and Llandough Hospital, National Health Service Trust, Penarth
4. Department of Pediatric and Adolescent Medicine, Mayo Clinic and Foundation, Rochester, Minnesota
5. Abteilung für Onkologie und Hämatologie, Olga Hospital, Stuttgart, Germany
6. Department of Pediatrics, University Hospital of Padova, Padova, Italy
7. Departments of Pediatrics and Biostatistics, Institut Gustave Roussy, Villejuif, France
8. Department of Paediatric Oncology, Royal Hospital for Children, Bristol, United Kingdom