GSTM1 and anemia (phenotype): Risk of anaemia (Hb < 7g/dL or Hb < 5g/dL) for a participant with a baseline haemoglobin level x g/dL who received a 0.4 mg/kg dose is slightly higher than for a participant with the same baseline haemoglobin level x g/dL who received a 0.25 mg/kg dose, and much lower than for a participant with (x − 1) g/dL haemoglobin level, who received a 0.25 mg/kg dose.