Proposed checklist.

<div><p>Background</p><p>Full coverage of childhood vaccines is a persistent challenge in low- and middle-income countries, suggesting the presence of specific contextual barriers. The emergence of the COVID-19 pandemic further worsened the situation. The complementary use of community-based participatory research (CBPR) and human-centered design (HCD) approaches has the potential to effectively create tailored interventions for improving public health outcomes. This protocol provides examples of methods to evaluate the use of these novel approaches in low- and middle-income countries. The ‘Let’s talk about vaccines’ project is a multisite community-based participatory project by VillageReach that uses the CBPR and HCD approaches to identify the barriers and co-create interventions/solutions to address under two routine immunization access and uptake in Malawi and Mozambique.</p><p>Methods</p><p>Guided by the Reach Effectiveness Adoption Implementation Maintenance (RE-AIM) framework, this evaluation prospectively evaluates the effectiveness (on under-two immunization coverage and related outcomes) of VillageReach’s co-created interventions and processes of implementation (reach, adoption, implementation and maintenance) in two districts in Mozambique and two in Malawi. This paper will also describe the theory of change for VillageReach’s project. Thematic analysis will be used to analyze the qualitative data, and interrupted time series analysis used to analyze the co-created interventions’ effectiveness on specific under two immunization outcomes. The analysis will integrate complex systems thinking and constructs inherent in health systems strengthening.</p><p>Discussion</p><p>This evaluation is an opportunity to share the use of novel and best practices, opportunities and challenges for improved community-responsive programming in routine immunization. It will be fundamental in providing evidence on the impact of interventions, evidence on mechanisms behind improvements in under- two immunization outcomes due to codesigned community-driven solutions and informing their scalability in similar contexts. Findings will inform the development of a comprehensive framework to guide the scalability of community-based approaches on childhood immunization uptake and access into similar contexts.</p></div>