Determinants of routine immunization costing in Benin and Ghana in 2011

Background: Existing tools to evaluate costs do not always capture the heterogeneity of costs at the facility level. This study seeks to address this issue through an analysis of determinants of health facility immunization costs. Methods: A statistical analysis on facility routine delivery and vaccine costs was conducted using ordinary least squares regression. Explanatory variables included the number of doses administered; proportion of time spent by facility staff on immunization; average staff wage; whether the health facility had enough staff; presence of cold chain equipment; distance to a vaccine collection point; and, facility ownership. Data were drawn from representative samples of primary care facilities in Benin and Ghana (46 and 50 facilities, respectively) collected as part of the EPIC studies. Results: Weighted average RI immunization facility cost was US$ 16,459 in Ghana and US$ 14,994 in Benin. The regression found total doses administered to be positively and significantly associated with facility cost in both countries. A 10% increase in doses resulted in a 4% increase in cost in Ghana, and a 7.5% increase in Benin. In Ghana, the proportion of immunization time, presence of cold chain, and sufficiency of staff were positively and significantly associated with total cost. In Benin, facility cost was negatively and significantly related to distance to the vaccine collection point. In the pooled sample, facilities in capital cities were associated with significantly higher costs. Conclusions: This study provides evidence on the importance of the level of scale in determining facility immunization cost, as well as the role of availability of health workers and time they spend on immunization in Ghana and Benin. This type of analysis can provide insights into the costs of scaling up immunization services, and can assist with development of more efficient immunization strategies.