Comparison of mean haemoglobin levels in different age groups, stratified by sex in relation to helminth- P. falciparum co-infection from one-way ANOVA and Kruskal-Wallis test. A: Comparison of mean haemoglobin (Hb) level in children aged 5-11 years (n = 224) shown for both sexes with different infection categories for hookworm (Hk) and P. falciparum (Pf). One-way ANOVA analysis showed significant differences in Hb for the total sample (not shown, p = 0.008) and in males (p = 0.028) B: Comparison of mean Hb level in participants aged 16-39 years (n = 243) shown for both sexes with different infection categories for S. mansoni (Sm) and P. falciparum (Pf). Kruskal-Wallis test showed significant differences in Hb for the total sample (not shown, p = 0.021) and in males (p = 0.015). Pregnant women (n = 31) were excluded from the analysis since pregnancy significantly lowers the Hb levels. In this sample of women aged 16-39 years, pregnant women had a mean Hb of 113.5 g/l vs. 123.3 g/l in non-pregnant women (p = 0.001).