**2. Materials and Methods**

#### *2.1. Study Design*

Each country implemented a qualitative study to identify the barriers and facilitators of vaccination faced by caregivers of zero-dose and under-immunized children, and to identify context-tailored solutions from the perspective of caregivers and other stakeholders. This study was implemented as part of the USAID-funded MOMENTUM Routine Immunization Transformation and Equity project, and a major objective of this study was to inform the design of locally tailored solutions to include in the project's activity workplans. We drew from participatory action research, intersectionality, and human-centered design (HCD) approaches to design a study that would ensure the engagement and collaboration of stakeholders at all levels. A key innovation was the inclusion of community-based cocreation workshops, which sought to validate initial study findings, build empathy for caregivers among other stakeholders, and use HCD tools to identify potential interventions to overcome barriers. Our approach aligns with draft guidance from UNICEF on integrating HCD into sub-national immunization coverage and equity assessments [22].
