[1] Erasmus MC Sophia Childrens Hosp, Pediat Oncol Hematol, Rotterdam, Netherlands
[2] Univ Milano Bicocca, Dept Clin Med & Prevent, Interfant Trial Data Ctr 99, Monza, Italy
[3] Univ Chile, Roberto del Rio Hosp, Chilean Natl Pediat Oncol Grp, PINDA, Santiago, Chile
[4] Hosp Pediat Prof Dr Juan P Garrahan, Dept Pediat Hematol Oncol, Buenos Aires, DF, Argentina
[5] Hop Univ Enfants Reine Fabiola ULB, Dept Hematooncol, Brussels, Belgium
[6] Great Ormond St Hosp Sick Children, UK Childrens Canc Study Grp, London, England
[7] Sheffield Childrens Hosp, Dept Paediat Haematol, Sheffield, S Yorkshire, England
[8] Univ Helsinki, Nord Soc Paediat Haematol & Oncol, Helsinki, Finland
[9] Univ Med Ctr Hamburg Eppendorf, Clin Pediat Hematol & Oncol, Hamburg, Germany
[10] Prince Wales Hosp, Hong Kong Paediat Haematol & Oncol Study Grp, Hong Kong, Hong Kong, Peoples R China
[11] Med Univ Sch, St Anna Childrens Canc Res Inst, A-1090 Vienna, Austria
[12] Med Univ Sch, St Anna Childrens Hosp, Dept Pediat, A-1090 Vienna, Austria
[13] Hop Robert Debre, Dept Pediat Hematol, Ft He FRALLE Grp, F-75019 Paris, France
[14] Italy Bambino Gesu Childrens Hosp, Assoc Italiana Ematol Oncol Pediat, Rome, Italy
[15] St Jude Childrens Res Hosp, 332 N Lauderdale St, Memphis, TN 38105 USA
[16] Berlin Frankfurt Munster Study Grp, Hannover, Germany
[17] Dana Farber Canc Inst, ALL Consortium, Boston, MA 02115 USA
[18] Czech Pediat Haematol, Prague, Czech Republic
[19] Australian & New Zealand Childrens Haematol & Onc, North Adelaide, Australia
[20] Med Univ Silesia, Polish Pediat Leukemia & Lymphoma Study Grp, Katowice, Poland
[21] Med Univ Silesia, Dept Pediat Hematol & Oncol, Katowice, Poland
[22] Princess Maxima Ctr Pediat Oncol, Utrecht, Netherlands
[23] Dutch Childhood Oncol Grp, The Hague, Netherlands