GSTM1 and anemia (phenotype): Baseline Hb was similar in the two groups (AMA1 group mean = 10.47, comparator mean = 10.35, t-test p = 0.311); however, when baseline Hb was examined in terms of adverse events graded according to the age-stratified grading scales, an uneven distribution of anaemia events in the groups at baseline was seen (see Table 5, Exact Wilcoxon-Mann-Whitney test p = 0.002).