From Concept to Clinic: The Long Road of Medical Device UX
Medical device UX development follows a structured, regulated process that looks nothing like consumer product design — and for very good reasons.
When I started work on the LUMA Vision Health Platform — a clinical interface for use in cardiac catheterisation procedures — one of the first things I did was map the full regulatory pathway from concept to clinical deployment. It was a humbling exercise.
Medical device UX in the US and EU is governed by specific usability engineering standards (IEC 62366 in the EU, as applied to FDA submissions) that define not just what the product must do, but how the design process must be conducted and documented. This is not optional, and it cannot be retrofitted.
Formative vs Summative Usability Testing
In consumer product design, user testing is typically an input to design decisions — you test, you learn, you iterate. In medical device design, usability testing has two distinct roles with different regulatory significance.
Formative testing — conducted during development — informs the design. Summative testing — conducted when the design is finalised — is the evidence that the design meets its intended use specification and doesn't introduce unacceptable use risks. On the LUMA Vision platform, our summative testing demonstrated an improvement in clinical task completion from 71% to 94% — a finding that carried weight in the regulatory submission.
Use Error Analysis
A use error is a user action that leads to an unintended outcome — different from a device malfunction in that the cause is human behaviour rather than technical failure. Usability engineering for medical devices requires a systematic analysis of potential use errors: what could go wrong, how likely it is, and how severe the consequence would be.
This analysis directly shaped several interface decisions on the LUMA platform. The placement of critical alerts, the design of confirmation dialogs for consequential actions, and the information hierarchy on the primary clinical display were all informed by the use error analysis rather than by conventional UX practice.
What Clinical UX Taught Me About Product Design Generally
The discipline of medical device UX — the rigour of the research process, the specificity of the documentation requirements, the seriousness with which edge cases are treated — has improved my product design practice outside of clinical contexts significantly.
The question 'what could go wrong with this interaction, and what would the consequence be?' is one that every product team should be asking — not just the ones building medical devices.
