Table 1.

Sample size for the health facility analysis and overview of the immunization registry system before and with the BID interventions

	Arusha Region, Tanzania		Southern Province, Zambia
	Pre-intervention	Post-intervention	Pre-intervention	Post-intervention
	n	n	n	n
Health facilities
Total number of health facilities in the region/province	253	253	253	253
Health facilities sampled for costing studya	43	34	52	46
Overview of the immunization registry system
Immunization registration	Relied on paper immunization registry	Electronic registration using a tablet	Relied on paper immunization registry	Electronic registration using a tablet
Immunization stock management	Paper-based immunization stock management system	Electronic management of vaccine stock using tablets and bar codes	Paper-based immunization stock management system	Electronic management of vaccine stock using tablets and quick response codes
Reporting	Paper reports submitted in person at the district	Reports automatically generated and submitted electronically	Paper reports submitted in person at the district	Reports automatically generated and submitted electronically

^aFewer facilities were available to participate in interviews at post-intervention compared to baseline. In Tanzania, at the time of the post-intervention assessment some of the facilities were still using the paper system only and so there was no difference from baseline; hence, we did not collect post-intervention data at these facilities. In Zambia, some facilities had not started using the electronic system at the time of post-intervention data collection, so they were also excluded from the post-intervention data collection. The number of facilities sampled at each time point are reported here