Strengthening national vaccine decision-making: Assessing the impact of SIVAC Initiative support on national immunisation technical advisory group (NITAG) functionality in 77 low and middle-income countries

Background: National Immunisation Technical Advisory Groups (NITAGs) are multi-disciplinary expert groups that provide policy-makers with independent, evidence-based advice on vaccination. Between 2008 and 2017, the SIVAC Initiative supported establishment and strengthening of NITAGs in low and lower-middle income countries though its impact was never assessed quantitatively. Aim: To quantitatively assess whether SIVAC support is associated with a faster rate at which NITAGs became functional based on six performance indicators. Methods: Data from the World Health Organization/Unicef Joint Reporting Form (JRF) from 77 low and lower-middle-income countries were used to examine the time delay between the start of SIVAC support and NITAG functionality using a Cox proportional hazards model. Results: Countries receiving SIVAC support took a mean of 2.00 (95% CI 1.40–2.60) years to reported functionality compared to 2.82 (95% CI 2.05–3.59) years for countries without SIVAC support. We found evidence that SIVAC support is associated with reduced time until NITAG functionality, and this association cannot fully be explained by GDP per capita, percentage of GDP spent on healthcare, or NITAG functionality score at the start of the study period. However, quality of JRF data for the questions used to calculate NITAG functionality were poor, particularly for countries not receiving SIVAC support. Conclusion: SIVAC support is likely to have enabled many countries to more rapidly achieve NITAG functionality.