Changes in %C3b-positive red cells, parasite prevalence, and parasite density with age. a.%C3b-positive red cells by age. For multiple comparison testing age groups >6 to ≤ 36 months were collapsed into one. P values were obtained by one-way analysis of variance adjusting for red cell CR1, red cell CD55, IC binding capacity, malaria status, and parasite density.* = 0.01 <P ≤ 0.05, ** = P < 0.01. Sidak correction for multiple comparisons was used. b. Prevalence of parasitemia by age group. c. Parasite density among malaria-positive individuals by age group. Parasite densities were Log10-transformed due to unequal variances between groups. Groups from >6 to ≤ 36 months of age were collapsed into one group and unadjusted comparisons between it and all other groups group were carried out. Sidak correction for multiple comparisons was used; ** = P < 0.01.