Randomization of clusters and allocation concealment
RECRUITMENT
On the basis of the health map, East Shoa zone has 10 rural woredas comprising of 159 health centers. Using a random number table generated in Excel software, a data manager, who was not member of the research team, randomly allocated three woredas for the intervention arm and the other three for the control arm, and then randomly selected one health center per woreda as clusters for the study. The non-adjacent catchment area health centers (clusters) selected were randomly allocated to the intervention and control arm by 1:1 ratio.Enrollment in the study was proposed to all eligible pregnant women attending antenatal visits during the recruitment period in the selected health facilities Systematic random sampling techniques were used to select participants by following KCluster randomization was used to prevent message contamination. Buffer zones (non-adjusted catchment area health centers) were also left between the intervention and control clusters to prevent information contamination. The intervention was blinded to pregnant women, counselor and data collector.