Incidence of malaria during the malaria transmission period among children who received at least one dose of IPT.

#estimated as 100×(1-HR) where HR is the hazard ratio from Cox regression, without covariate adjustment. Efficacy against the first episode of malaria, adjusted for effects of bednet use, centre and age at enrolment was 54% (37%,66%), compared with an unadjusted estimate among the subset of individuals with non-missing covariate data of 51% (33%,64%). The corresponding estimates for the first episode of malaria >5000/uL were 58% (31%,74%), compared with 56% (28%,73%) unadjusted; for all episode of malaria, 52% (38%,63%) compared to 50% (33%,63%) unadjusted; and for all episodes of malaria >5000/uL, 58% (32%,74%), compared to 55% (27%,73%) unadjusted.