Accessibility as a clinical standard

WCAG tells you a button needs enough contrast. It doesn't tell you that a pulsing animation can trigger a seizure, or that someone in post-seizure fog can't make sense of a dense alert.

We were also scaling into a multi-brand system. Without a shared baseline, each brand could quietly lower the bar: a lighter grey here, a smaller label there. Nobody would notice until it shipped.

Rather than working down the WCAG checklist, I started with our users. I mapped each area of accessibility to the impairments common in our population: medication side effects like tremor and blurred vision, temporary effects after a seizure, cognitive comorbidities, and older caregivers with declining eyesight.

Each section of the standard opens with who it protects and roughly what share of our users that is. So the case for every rule is about people, not compliance.

The most important decision was separating what brands can change from what they can't. Brands keep control of colour, typeface, component styling and motion style. Contrast, type minimums, 48dp tap targets, screen reader behaviour, motion limits and safety patterns are fixed for everyone.

That gave brand teams real freedom, and gave engineering and QA a clear rule to check against.

Some rules go beyond WCAG because the risk is clinical.

• Photosensitivity: no flashing or pulsing elements, no high-contrast stripes, and animations capped at 300ms.
• Therapy status: always colour, icon and label together, and never more than one tap away. Paused therapy is calm grey, not alarm red.
• Alerts: one clear action, no toasts that vanish in under three seconds, and every status change announced to TalkBack.

A standard only works if nobody has to remember it. So rather than adding a review at the end, we built it into the workflow: accessibility criteria on every ticket and in the Definition of Done, Figma annotations for reading order and states before handoff, and no brand component merged without a global accessibility review.

The design system is where it's enforced. Colour tokens record their contrast in light and dark mode, and components ship with tap targets and 200% text scaling built in. The design system itself grew out of this work. I set the direction with Iro Mavrogeni and Rebecca Shubert, and made the case for it before there was a plan. Iro has done much of the heavy lifting since, taking it to where it is today, and recently presented it to our R&D teams with accessibility as a core benefit.

The same thinking shaped the tone of voice I wrote for the VNS Therapy app. It starts from a simple idea: people who are tired, medicated or post-seizure still need to understand what we're telling them.

• [The standard now applies across X products and brands]
• [Accessibility criteria are part of the Definition of Done for X teams]
• [Issues now caught in design review rather than after release]
• [Used as the reference by other teams and contract copywriters]

The shift that mattered most was treating accessibility as patient safety rather than compliance. It's a much harder thing to deprioritise. Next, I want to test the standard directly with patients and caregivers, to see where the rules hold up in real use.