Calculations
malaria, infection
MALARIA, INFECTION
Based on the demographic data to be confirmed in the preceding census, the clusters are planned to include approximately 420 people, of which 280 will be above 4–5 years of age and potentially eligible for treatment and 140 will be children under 5 potentially eligible for follow-up. There will be 53 clusters per arm in Mozambique.Clusters in Mozambique will be randomized in three arms, resulting in inclusion of approximately 45,000 participants to receive treatment or control and approximately 2000–4000 children to be followed for 6 months.With this sample size, the study has 80% power at 5% significance to detect a 20% reduction in malaria incidence infection, from 4.20 cases/child-year at risk to 3.36 for the human-only intervention, using a coefficient of variation (km) of 0.35 for Mopeia/Mozambique. This value for km has been back-calculated from a cluster randomized trial recently conducted in the same study site [For the human and livestock intervention, this sample size has 80% power to detect a further 20.5% reduction in malaria incidence infection between the human and human + livestock intervention arms, from 3.36 cases/child-year at risk (the lower incidence expected in the human only arm) to 2.67.The total number of clusters needed per arm has been increased by one for all scenarios to account for potential LFU of a whole cluster (withdrawal of community consent, displacement, etc.)