GSTM1 and anemia: Compared to iron sucrose for anemia, iron isomaltoside demonstrated comparable Hb responder (SMD=1.41; 95% CI=0.71 to 2.81; P=0.33; Figure 3), serum ferritin (SMD=15.13; 95% CI=-23.45 to 53.71; P=0.44; Figure 4), transferrin saturation (SMD=1.20; 95% CI=-1.08 to 3.47; P=0.30; Figure 5).