AbstractIntroductionClear communication of diagnostic test results and dementia diagnosis is challenging yet important to empower patients and care partners. A personalized diagnostic report could support the communication of dementia diagnostics and aid patients’ understanding of diagnosis. In this study, we aimed to design a diagnostic report in co‐creation with patients and care partners.MethodsWe used a mixed‐methods approach, combining surveys with focus groups in iteration. Phase 1 consisted of an international survey assessing needs among patients (n= 50) and care partners (n= 46), and phase 2 consisted of focus group meetings (n= 3) to co‐create the content and to hands‐on co‐design the layout of the diagnostic report with patients (n= 7) and care partners (n= 7). Phase 3 validated results from phase 2 in a survey among patients (n= 28) and care partners (n= 12), and phase 4 comprised final feedback by dementia (care) experts (n= 5). Descriptive statistics were used to report quantitative results and directed content analysis was used to analyze qualitative data.ResultsMost patients (39/50, 78%) and care partners (38/46, 83%) positively valued a diagnostic report to summarize test results. The report should be brief, straightforward, and comprise results of the diagnostic tests, including brain imaging and information on future expectations. Despite a clear preference for visual display of test results, several visualization options were deemed best and were equally comprehended.DiscussionIn this study, we developed a prototype of a personalized patient report through an iterative design process and learned that co‐creation is highly valuable to meet the specific needs of end‐users.