The Impact of Pop-up Location and Mask Transparency on the Visual Search Efficiency of Telehealth Interfaces

Pop-up interfaces are crucial for information confirmation and decision support in telecare, yet their visual usability across task contexts remains underexplored. This study investigates how pop-up window position and background mask transparency jointly influence visual search performance and user experience. We conducted a 2 (position: center vs. bottom) × 3 (mask transparency: 20%, 35%, 50%) between-subjects experiment with 60 participants and analyzed the data using two-way ANOVA. Results show task-dependent effects. For tasks not requiring information comparison, a centered pop-up with 50% mask transparency helps users focus on in-window decision making. For information confirmation or higher-complexity tasks, 35% mask transparency—combined with task-appropriate positioning—better supports attention allocation and task execution. These findings provide actionable guidance for telecare interface design, emphasizing adaptive pop-up configurations rather than a one-size-fits-all approach.