[1] Princess Maxima Ctr Pediat Oncol, Pediat Oncol, Utrecht, Netherlands
[2] Univ Med Ctr Utrec, Wilhelmina Childrens Hosp, Dept Anesthesiol, Utrecht, Netherlands
[3] Univ Med Ctr Utrecht, Wilhelmina Childrens Hosp, Dept Pediat, Utrecht, Netherlands
[4] Univ Med Ctr Groningen, Dept Pediat Oncol hematol, Groningen, Netherlands
[5] Leiden Univ, Math Inst, Leiden, Netherlands
[6] Univ Med Ctr Utrecht, Wilhelmina Childrens Hosp, Dept Pediat Intens Care, Utrecht, Netherlands