From global guidance to local action: Evaluating the use and uptake of an urban immunization toolkit using human-centered design in Nigeria

Over half the global population lives in urban areas, projected to reach 70% by 2050. Urban poor populations face immunization gaps due to mobility, governance challenges, and limited healthcare access. The Urban Immunization Toolkit (2018) was developed to support district-level managers in addressing these challenges, yet there is limited empirical evidence on how such global toolkits are used, adapted or implemented in urban contexts, and specifically perspectives of end users, particularly district-level program managers remain underexplored. This study addresses this gap by examining the toolkit’s real-world application across multiple settings. Using human-centered design, this study assessed the toolkit’s use across four domains: effectiveness, adaptability, value-added, and ease of use. Phase 1 (June 2023–March 2024) included a global survey with 23 respondents from eight countries. Phase 2 (March–August 2024) involved co-creation workshops in Lagos and Edo States, Nigeria, with caregivers of zero-dose children, immunization managers, and policymakers who applied the toolkit to address challenges related urban immunization in their local contexts. Phase 1 survey respondents rated the toolkit favorably across all domains, though qualitative feedback revealed weaker perceptions about its effectiveness and adaptability. Workshop participants in Phase 2 emphasized the need for context-specific strategies, simpler language, and private sector engagement guidance. Across both phases, participants recommended clearer adaptation guidance, practical job aids, regular updates with country-specific feedback to create a living catalog of solutions, multilingual translation of the toolkit, and its integration into national-level policy guidelines to increase accessibility and use across all levels of government. Findings from both phases informed recommendations to revise the toolkit’s usability and uptake, while also showcasing the application of human-centered design approaches to adapt and evaluate toolkits. These results contributed to the revision and release of a revised toolkit in 2026.From a policy and practice perspective, these findings underscore the importance of designing global implementation tools with built-in flexibility and embedding local co-creation processes that actively engage end users, such as district managers and frontline implementers, to adapt tools and guidance to their operational contexts. At the same time, these tools must align with existing institutional systems to effectively support district-level decision-making. At the global level, the findings highlight the need for ongoing iteration, expanded access to evidence-based toolkits for end users, and sustained collaboration with countries and implementing partners. Systematically capturing and sharing lessons learned from urban immunization strategies would strengthen the evidence base, support continuous program improvement, and inform the development of policy decisions and evidence-based tools.