Who, Where, What, and How to Nudge: A Systematic Review of Co-Designed Digital Nudges for Behavioral Interventions

Digital nudges refer to subtle modifications in digital choice architectures that are increasingly applied across domains such as healthcare, human–computer interactions, and behavioral science. However, existing approaches often overlook users’ needs, contextual factors, and ethical considerations related to transparency and autonomy. This systematic literature review, guided by PRISMA 2020, examines the integration of co-design methodologies in digital nudging across four dimensions: participants, application domains, nudge forms, and development methods. The findings show that co-design is primarily driven by end-users, supported by domain experts and technology specialists. Applications are concentrated in health-related contexts, particularly chronic disease management and mental health. The effectiveness of priming varied across studies, with some reporting short-term benefits and others indicating user fatigue, suggesting context-dependent impact and limited long-term effectiveness.