Bringing Plain Language Principles Into Interaction Design Practices: Insights From A Wizard of Oz Approach

Language, whether textual, verbal, or visual, can become a barrier to access and understanding in human-computer interaction when not effectively designed or tailored to users' needs. One way to address these communication barriers is to adopt Plain Language guidelines to help users find, comprehend, and use vital information. This study investigated the challenges development teams face when applying PL principles to the design of interactive systems. Using the Wizard of Oz technique, we simulated a chatbot supporting novice developers in implementing PL in health-related applications. The results highlight challenges in addressing diverse literacy levels and extending PL beyond text to visual and interaction design aspects. Based on these findings, we identify four central challenges that have not been previously mapped in the literature and propose design recommendations grounded in empirical evidence from novice development teams.