Co-Designing a Digital Intervention for Health Promotion for People With Intellectual Disabilities: Qualitative Study of Team Members’ Reflections

BACKGROUND: People with intellectual disabilities experience a disproportionate burden of preventable health conditions, often linked to low levels of physical activity and poor dietary habits. Although digital health interventions hold considerable promise for addressing these challenges, many existing solutions remain difficult to use for this population due to limited accessibility. Co-design is increasingly advocated to develop digital health solutions that better align with users' needs, yet there is limited empirical guidance for co-design processes with people with intellectual disabilities. OBJECTIVE: This study aimed to explore experiences of a co-design process for developing a digital intervention for health promotion for people with intellectual disabilities, from the perspectives of members of the co-design team involved in different roles across the process. METHODS: A qualitative study design was used based on 5 retrospective reflection meetings conducted in southeastern Sweden following a co-design process of 17 workshops. Eight purposively selected members of the multidisciplinary co-design team, including 4 researchers, 2 user experience designers, 1 support worker, and 1 coresearcher with intellectual disability, participated in different constellations. Reflection meetings were held between February and March 2026, and transcribed data were analyzed inductively and interpreted in relation to established co-design frameworks. RESULTS: The findings reflect the team members' experiences of the co-design process and point to a number of factors that appeared to support participation and collaboration. These included an extensive preparatory phase focused on recruitment and relationship building, the importance of working concretely and visually already during predesign, and the role of convivial relational practices in supporting confidence, voice, and collaboration. Time demands were mainly related to the iterative and participatory nature of co-design rather than to intellectual disability per se. Ethical considerations related to compensation were also highlighted, particularly in relation to recognizing coresearchers' contributions on equal terms. CONCLUSIONS: By examining experiences of the co-design process, this study contributes methodological insights into how digital intervention development can be made more accessible, participatory, and responsive to the needs of people with intellectual disabilities. The findings suggest that enabling meaningful co-design with people with intellectual disabilities requires flexible interpretation of existing co-design frameworks, sustained attention to relational collaboration throughout the process while recognizing the ongoing importance of collaboration with support workers, and adaptation of methods rather than a need for development of entirely new ones. Supporting a sense of collaboration and conviviality over time, alongside addressing ethical issues of compensation for coresearchers' work, may be critical for producing digital interventions for health promotion that are both usable and inclusive.