GSTM1 and malaria: However, in other findings among children (<5 years) who were exposed to between 1 and 2 years of malaria control, mean relative risk for Hb < 11 g/dL was 0.73 (95% CI 0.64–0.81) and 0.40 (95% CI 0.25–0.55) for hemoglobin < 8 g/dL [48–50].