Lead-Dx: Development and evaluation of a simulation-based education codesign framework to address diagnostic excellence for all

Background While accurate diagnoses are fundamental to healthcare, errors affect estimated 12 million people yearly, with harms underestimated among marginalized persons. Codesign offers a promising educational solution. Methods A simulation codesign framework was developed. Evaluation included team psychological safety, codesign principal alignment, and scenario quality. Results Learning equity, addressing disparities in diagnosis (Lead-Dx) is a process-oriented, structured framework in which faculty collaborate with standardized patients with lived experiences of diagnostic inequity. Lead-Dx supports psychologically safe team environments, aligns with codesign principles, and yields valid scenarios. Conclusion Lead-Dx is an actionable framework that addresses diagnostic inequity through collaborative SP-faculty simulation codesign.