GSTM1 and anemia (phenotype): Using linear regression analysis with fixed effects we found that LOS (p < 0.001) and postoperative administration of RBC units (p < 0.001) were predictors for delayed mobility but not gender, age, preoperative Hb level, severity of anaemia, CRP level, ASA, preoperative Hb increase, and intraoperative administration of RBC units (Supplemental Fig. 10).