11 variables determined at the onset of acute lymphocytic leukaemia were tested to predict disease‐free survival in 267 children. All children had received similar induction treatment and basic maintenance therapy, whereas 5 different reinforcement treatments were administered irrespective of the severity of the disease at onset. Three modes of prophylactic central nervous system treatment were employed. The risk of relapse was significantly increased for leucocyte count above 50 times 109/1, lymphoblasts above 80% in peripheral blood, age below 2 years or over 5 years, and for males. The risk of relapse was increased by estimated factors of 1.9, 2.3, 1.7, and 1.7, respectively.
When the above 4 variables were included in the model, no further prognostic value was demonstrated for haemoglobin concentration, platelet count, signs of bleeding in the skin, mucous membranes or intracranially, presence of leukaemic infiltrations outside the bone marrow, hepatosplenomegaly, mediastinal mass, or T‐ or B‐cell leukaemia. However, evaluation of T‐ or B‐lymphoblast type impact was hampered by small numbers.