Survival rates of groups subjected to 7-min. ischaemia (A) and 9-min. ischaemia (B) are illustrated using Kaplan–Meier survival curves. 7C: control group subjected to 7-min. ischaemia; 7E: EPO group subjected to 7-min. ischaemia; 9C: control group subjected to 9-min. ischaemia; 9E: EPO group subjected to 9-min. ischaemia. Survival rates at day 2 after SCI were 70.6%, 68.8%, 73.3% and 74.3%, and 65.5%, 63.0%, 62.9% and 63.7% at day 7 in the 7C, 7E, 9C and 9E groups, respectively. There were no significant differences in survival rate between groups 7C and 7E (P= 0.797) or between groups 9C and 9E (P= 0.971), according to the Log-rank test.