Determinants of Wealth Related Inequalities in Full Childhood Vaccination in Nepal: A Decomposition Analysis Using Nepal Demographic and Health Survey (NDHS) 2022

Background Over the past two decades, child health indicators in Nepal have improved significantly at the national level. Yet, this progress hasn't been uniform across various population subsets. This study identified the determinants associated with childhood full vaccination, assessed wealth-related inequalities, and delved into the key factors driving this inequality. Methods Data for this study were taken from the most recent nationally representative Nepal Demographic and Health Survey 2022. A total of 959 children aged 12–23 months who had received routine childhood vaccinations as per the national immunisation program were considered for analysis. Binary logistic regression models were conducted to identify the associated factors with outcome variable (uptake of full vaccination). The concentration curve and Erreygers normalized concentration index were used to assess inequality in full vaccination. Household wealth quintile index scores were used to measure wealth-related inequality in households. Decomposition analysis was conducted to identify determinants explaining socio-economic inequality in the uptake of childhood vaccination. Results The coverage of full vaccination among children was 79.8% at national level. Several factors, including maternal health service utilisation variables (e.g., antenatal care, institutional delivery), financial challenges related to visiting health facilities, and mothers' awareness of health mother group meetings within their ward, were associated with the uptake of full vaccination coverage among children. The concentration curve was below the line of equality, and the relative Erreygers normalized concentration index was 0.090, indicating that full vaccination was disproportionately higher among children from wealthy groups. The decomposition analysis identified institutional delivery (20.21%), the money needed to visit health facilities (14.25%), maternal education (16.79%), maternal age (8.53%), and caste (3.03%) were important contributors to wealth related inequalities in childhood full vaccination uptake. Conclusions There was notable socioeconomic inequality in full vaccine uptake among children in Nepal. Multisectoral actions involving responsible stakeholders are pivotal in reducing the inequalities, including promoting access to maternal health services and improving educational attainment among mothers from socioeconomically disadvantaged communities.