Edge Cases in Health Systems: How Do You Design Error Screens and Critical Health Alerts?

Engineering leaders working on medical apps know that Edge Cases aren't a "Nice to Have" – they're an existential requirement. In a medical system, an unclear error screen can lead to a misdiagnosis, a broken Workflow, or a user who doesn't realize that test results require urgent attention. Many designs that come out of R&D fail at exactly this point: the designer showed a beautiful dashboard for the normal state, but never planned for the dozens of edge and error states. While working on Ichilov's Movement, from the very first stage of the specification we were required to document every possible error state. If the server is unavailable mid-test – what does the user see? If a test result requires immediate attention from a doctor – how does the system distinguish between a routine alert and a critical one? If the user opened the app after a period of inactivity – do they need to re-authenticate? For each such case, we designed dedicated UI components, with a distinct visual hierarchy that helps the user immediately understand the severity of the situation. Critical alerts were designed in a distinct color (not just red – red was reserved only for genuine emergencies), with clear micro-copy that tells the user what to do. Non-critical errors were designed in a softer tone, with suggested solutions. For CTOs, the key insight is: require your designers to provide detailed documentation of edge cases as part of the development handoff package. If the designer doesn't begin the work by mapping edge cases – you're going to get a system that breaks your team at the development stage.