Distribution of EWALL-PI by trial and within each trial immunophenotype, relapse, and death. (A) The dotted vertical line shows the median EWALL-PI for each trial. The UKALL14 distribution was significantly different to GIMEMA-LAL1913 (P < .001) and PETHEMA-ALL-HR2011 (P < .001) but not NILG-ALL10/07 (P = .73) (P values from a Kolmogorov–Smirnov test for equality of distribution). (B) There was no difference between the EWALL-PI distributions for patients with B-ALL and T-ALL within each trial. (C) The median EWALL-PI values for patients treated on UKALL14, GIMEMA-LAL1913, and PETHEMA-ALL-HR2011 who relapse was significantly greater than those patients who did not relapse. (D) Similarly, the median EWALL-PI values for patients treated on UKALL14, NILG-ALL10/07, and PETHEMA-ALL-HR2011 who died was significantly greater than those patients who did not die. The P values reported in boxes B, C and D are from a Mann-Whitney U test because the EWALL-PI was not normally distributed using a Shapiro-Wilk Test for normality.