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NDC-2026-001 v0.1

The Neurodiversity Design Standard

Seven domains. 35 criteria. 140 maximum points. The full assessment framework for neurodiversity-inclusive digital design.

NDC-2026-001 v0.1 (pre-release)

How the standard works

Each criterion is scored from 0 (not met) to 4 (exemplary). Every score is supported with specific evidence from the assessment. The total possible score is 140 points.

Reviewed: Any score. Full report provided. 12-month validity.

Endorsed: 50%+ overall (70+ points), no domain below 1.5 average. 18-month validity.

Certified: 75%+ overall (105+ points), no domain below 2.5 average, review by an independent panel of neurodivergent professionals. 12-month validity with annual renewal.

All 7 domains and 35 criteria

How we test

Every NDC assessment combines lived experience with professional-grade technical testing. Our assessors are neurodivergent, and they are also technically skilled practitioners who test with the same tools and methods used in formal accessibility audits.

Assistive technologies

Assessments include testing with NVDA, JAWS, VoiceOver (iOS/macOS), TalkBack (Android), and ZoomText. We test how products behave when used with the assistive technologies neurodivergent people actually rely on.

Evaluation tools

Automated checks are run using axe DevTools, WAVE, and Siteimprove. Colour Contrast Analyser (CCA) is used for visual checks. PDF documents are tested with PAC (PDF Accessibility Checker) and Adobe Acrobat Pro.

Manual testing

Keyboard-only navigation is tested as standard on every assessment. We verify that all functionality is accessible without a mouse. We also test at multiple zoom levels (up to 400%) and with prefers-reduced-motion enabled.

Mobile accessibility

Products with mobile apps or responsive web interfaces are tested on iOS and Android with VoiceOver and TalkBack enabled. Touch target sizes, gesture alternatives, and mobile-specific navigation patterns are assessed.

WCAG criteria our testing covers

Our manual and automated testing covers the following WCAG 2.2 AA success criteria as part of every NDC assessment:

Keyboard (2.1.1, 2.1.2, 2.4.3, 2.4.7, 3.2.1)

Zoom and reflow (1.4.4, 1.4.10)

Colour and contrast (1.4.3, 1.4.11)

Text alternatives (1.1.1)

Audio and video (1.2.1, 1.2.2, 1.2.5)

Motion (2.2.2, 2.3.1)

Forms (1.3.1, 3.3.1, 3.3.2)

Headings and structure (1.3.1, 2.4.6)

In addition to WCAG, the NDC standard tests for cognitive load, executive function support, sensory overload prevention, emotional safety, dark pattern absence, notification respect, and personalisation. These are the areas WCAG does not reach.

D1 Cognitive Load and Information Architecture +

How much mental effort the product demands and how well information is organised.

D1.1
Information density
Screens present an appropriate amount of information without overwhelming the user. Content is chunked, spaced, and prioritised.
D1.2
Navigation clarity
The navigation structure is logical, shallow, and predictable. Users can find what they need without excessive decision-making.
D1.3
Decision complexity
The number of choices presented at any point is manageable. Options are clearly differentiated and the consequences of each are explained.
D1.4
Progressive disclosure
Complex information is revealed in stages rather than all at once. Users can access detail when they need it without being forced to process it upfront.
D1.5
Distraction management
The interface minimises unnecessary visual noise, competing animations, auto-playing content, and unsolicited interruptions.
D2 Reading and Language Accessibility +

Whether content is legible and understandable for users with dyslexia, ADHD, or processing differences.

D2.1
Typography quality
Font choices, sizes, spacing, and contrast support comfortable reading. Body text is at least 16px with adequate line height and paragraph spacing.
D2.2
Plain language
Content uses clear, direct language appropriate to the audience. Jargon is avoided or explained. Sentences are concise.
D2.3
Reading flow and structure
Content has clear headings, subheadings, summaries, and signposting. Users can scan and locate information without reading everything.
D2.4
Abbreviation and acronym handling
Abbreviations and acronyms are expanded on first use and are accessible throughout via tooltips, glossaries, or inline definitions.
D2.5
Alternative formats
Key content is available in more than one format (text, audio, video, visual summary) to accommodate different processing preferences.
D3 Sensory Design +

How the product handles visual, auditory, and motion elements for sensory-sensitive users.

D3.1
Colour and contrast
Colour is not the sole means of conveying information. Colour contrast ratios are tested against WCAG AA thresholds using dedicated contrast analysis tools. Colour palettes avoid combinations known to cause visual stress.
D3.2
Motion and animation
Motion is purposeful, not decorative. Users can pause, stop, or reduce animations. The product respects prefers-reduced-motion.
D3.3
Audio management
Audio does not auto-play. Volume controls are accessible. Audio content has captions or transcripts.
D3.4
Visual complexity
Interfaces avoid visual clutter, excessive decoration, and competing focal points. Visual hierarchy is clear and consistent.
D3.5
Sensory overload prevention
The product provides mechanisms to reduce sensory input (quiet modes, simplified views, notification controls) and does not create cumulative sensory fatigue.
D4 Predictability and Consistency +

Whether the product behaves reliably and builds user confidence through consistent patterns.

D4.1
Interface consistency
Interactive elements look and behave the same way throughout the product. Buttons, links, and controls follow consistent patterns.
D4.2
Navigation stability
Navigation structure does not change unexpectedly between sections or states. Users always know where they are and how to get back.
D4.3
Feedback and confirmation
The product provides clear, immediate feedback for user actions. Success, error, and loading states are communicated explicitly.
D4.4
Expectation setting
The product tells users what will happen before they take an action. Destructive actions require confirmation. Consequences are stated in advance.
D4.5
Error recovery
Errors are communicated clearly with specific guidance on how to fix them. Error messages appear next to the relevant field, not in a separate location.
D5 Executive Function Support +

How well the product supports planning, sequencing, and task completion for users with executive function differences.

D5.1
Task breakdown
Complex processes are broken into clear, numbered steps with progress indicators. Users can see where they are and how much remains.
D5.2
Save and resume
Users can save their progress and return later without losing work. Session timeouts are generous and clearly communicated.
D5.3
Time management
Timed elements can be paused, extended, or removed. No artificial urgency or countdown pressure unless genuinely required.
D5.4
Prioritisation support
Where users must complete multiple tasks, the product helps them understand priority, sequence, and deadlines.
D5.5
Default settings
Default settings are safe, accessible, and sensible. Users are not required to configure the product extensively before it becomes usable.
D6 Emotional Safety and Trust +

Whether the product respects user wellbeing, avoids manipulation, and builds genuine trust.

D6.1
Dark pattern absence
The product does not use manipulative design patterns including fake urgency, forced continuity, hidden costs, confirmshaming, or misdirection.
D6.2
Error tone
Error messages and system communications are neutral, supportive, and non-blaming. The product does not make users feel stupid or at fault.
D6.3
Notification respect
Notifications are controllable, proportionate, and respectful. Users can adjust frequency, channels, and types. Marketing notifications are opt-in.
D6.4
Privacy and consent clarity
Data collection is transparent. Consent mechanisms are clear and genuinely optional. Users understand what they are agreeing to.
D6.5
Supportive onboarding
New users are guided without being overwhelmed. Help is accessible but not forced. The product assumes competence while offering support.
D7 Flexibility and Personalisation +

Whether users can adapt the product to their own needs and assistive technology requirements.

D7.1
Display customisation
Users can adjust text size, spacing, contrast, and colour scheme. The product supports system-level accessibility settings.
D7.2
Layout flexibility
Content reflows correctly at different zoom levels and screen sizes. No horizontal scrolling at up to 400% zoom.
D7.3
Input flexibility
The product supports multiple input methods (keyboard, mouse, touch, voice) without degrading the experience for any of them.
D7.4
Assistive technology compatibility
The product works correctly with screen readers, magnifiers, switch devices, and other assistive technology. ARIA attributes are correctly implemented.
D7.5
User preference persistence
User customisations and preferences are saved and applied consistently across sessions and devices.

Co-existing conditions and digital design

Neurodivergent conditions rarely travel alone. ADHD, autism, dyslexia, and dyspraxia frequently co-occur with each other and with a range of other conditions that affect how people process information, perceive sensory input, and interact with digital products. Our assessors are trained to understand this broader picture, and the NDC standard is designed to catch the design failures these conditions create.

Irlen syndrome+

A difference in the brain's ability to process visual information, particularly affecting reading and printed text. Bright white backgrounds, certain colour combinations, and dense text blocks can cause significant visual stress, distortion, and fatigue.

NDC assessment covers: D2 (typography, line spacing, reading flow), D3 (colour choices, visual stress), D7 (user control over display settings).

Alexithymia+

A difficulty accurately identifying or describing emotions. Estimated to affect around 50% of autistic adults. Products that assume users can name their emotional state create unnecessary barriers.

NDC assessment covers: D6 (error tone, feedback language, emotional assumptions), D2 (plain, direct language).

Aphantasia+

The inability to visualise mental imagery. People with aphantasia cannot picture a scene, recall a face, or see something in their mind's eye. Products relying on visual metaphors without text alternatives create barriers.

NDC assessment covers: D2 (alternative formats, multi-modal information), D1 (information presentation and structure).

Auditory processing disorder (APD)+

Hearing is fine but the brain has difficulty filtering and interpreting sound. Products relying on audio-only content or voice interfaces without text alternatives are problematic.

NDC assessment covers: D3 (audio management, captions, transcripts), D2 (alternative formats), D7 (multiple interaction methods).

Prosopagnosia (face blindness)+

Great difficulty recognising faces, even those seen many times. Products using face-based identification, photo-only profiles, or video-first communication without name labels create significant barriers.

NDC assessment covers: D3 (visual information not sole means of identity), D4 (clear labelling), D1 (mental effort for navigation).

Rejection sensitive dysphoria (RSD)+

Very common with ADHD. Extreme emotional sensitivity triggered by perception of rejection or criticism. Error messages that blame the user, punitive form validation, and social features highlighting exclusion can trigger intense distress.

NDC assessment covers: D6 (error tone, dark pattern absence, confirmshaming, supportive onboarding).

Synaesthesia+

Two or more senses involuntarily joined together, for example seeing colours when hearing sounds. Products using colour inconsistently between sections can create confusion and sensory conflict.

NDC assessment covers: D4 (consistent use of colour and patterns), D3 (visual complexity, sensory overload prevention).

Sensory processing disorder (SPD)+

The brain has difficulty integrating sensory information, causing extreme reactions to sensory input. Bright screens, auto-playing media, notification sounds, and visually cluttered interfaces can cause significant distress.

NDC assessment covers: D3 (all five criteria including sensory overload prevention, motion control, audio management), D7 (display customisation, preference persistence).

Central auditory processing disorder (CAPD)+

Specifically affects the central nervous system's ability to process auditory information. Video calls, voice-based interfaces, and audio-only tutorials are particularly challenging.

NDC assessment covers: D3 (captions, transcripts, audio management), D2 (alternative formats), D5 (multiple ways to engage).

Developmental language disorder (DLD)+

Affects language development into adulthood. People may have difficulty understanding complex sentences, processing written instructions, or expressing themselves in writing.

NDC assessment covers: D2 (plain language, reading flow, structure), D1 (information density, progressive disclosure), D2.5 (alternative formats).

Dysgraphia+

Difficulties with letter formation, word spacing, and translating ideas into written language. Products requiring extensive typing with no voice-to-text alternatives or penalising spelling errors create unnecessary friction.

NDC assessment covers: D7 (input flexibility, multiple input methods), D5 (save-and-resume, task breakdown), D4 (error recovery and tolerance).

Tourette syndrome+

Involuntary movements and vocalisations (tics). Products with very small click targets, timed interactions, or interfaces requiring sustained fine motor precision can be particularly difficult.

NDC assessment covers: D5 (time management, removal of artificial pressure), D7 (input and layout flexibility), D3 (audio management, alternative interactions).

Sluggish cognitive tempo (SCT)+

Excessive daydreaming, slow processing of information, difficulty staying alert, and poor memory retrieval. Products requiring sustained concentration or presenting information quickly without the option to slow down are particularly challenging.

NDC assessment covers: D1 (information density, progressive disclosure), D5 (time management, save-and-resume), D4 (navigation stability, clear feedback).

Pathological demand avoidance (PDA)+

A profile within the autism spectrum characterised by extreme avoidance of everyday demands. Mandatory sequences, forced tutorials, and language framing interactions as obligations rather than choices can trigger significant avoidance responses.

NDC assessment covers: D6 (supportive onboarding, dark pattern absence), D5 (default settings, unnecessary forced steps), D7 (user control and choice).

A note on co-occurring mental health conditions: anxiety, depression, PTSD, autistic burnout, and ADHD burnout are extremely common alongside neurodivergent conditions. While the NDC does not assess for mental health outcomes directly, our D6 (Emotional Safety and Trust) domain specifically evaluates whether digital products contribute to or reduce psychological distress. Products that use manipulative design, create artificial urgency, or punish users for errors can worsen existing mental health conditions. Our assessments are designed to catch these patterns.

How NDC relates to existing standards

The NDC standard does not replace any existing accessibility framework. It fills a specific gap that none of them currently cover: structured, scorable assessment of digital products for neurodivergent users. Here is how it sits alongside the standards that already exist.

WCAG 2.2

W3C Recommendation

What it covers: The global standard for web accessibility. Primarily addresses visual, auditory, and motor accessibility. Referenced in law across the UK (Equality Act), EU (European Accessibility Act), and internationally (EN 301 549).

What it does not cover: Cognitive load management, executive function support, sensory overload prevention, emotional safety, dark pattern detection, and neurodivergent-specific usability. WCAG includes some cognitive criteria (headings, error identification, input assistance) but cognitive accessibility is not its primary focus.

NDC relationship: Complementary. A product should meet WCAG 2.2 AA and the NDC standard for comprehensive accessibility coverage. We recommend both. WCAG compliance is not a prerequisite for NDC assessment, but we note WCAG status in every report.

W3C COGA Guidance

W3C Working Group Note

What it covers: "Making Content Usable for People with Cognitive and Learning Disabilities" provides design guidance across 8 objectives including clear purpose, findability, understandable content, error avoidance, focus support, memory reduction, help and support, and personalisation.

What it does not cover: COGA is guidance, not a testable standard. It has no scoring mechanism, no pass/fail thresholds, no certification, and no assessment methodology. It covers cognitive and learning disabilities broadly (including intellectual disabilities, acquired brain injuries, and age-related decline) rather than neurodiversity specifically.

NDC relationship: The NDC standard draws on COGA's evidence base and aligns with several of its objectives. Where COGA provides design patterns and recommendations, NDC operationalises them into a structured, scorable assessment framework with specific criteria, evidence requirements, and certification thresholds. COGA tells you what to think about. NDC tells you whether you have actually done it.

EN 301 549

European Standard

What it covers: The European harmonised standard for ICT accessibility. References WCAG 2.1 for web content and adds requirements for software, hardware, documentation, and support services. It is the standard used to demonstrate compliance with the European Accessibility Act.

NDC relationship: Complementary. EN 301 549 provides the regulatory baseline for European markets. NDC assessment covers the neurodivergent-specific dimensions that EN 301 549 does not address. For organisations selling digital products into the EU, both are relevant.

BS 8878

British Standard

What it covers: A process standard for embedding accessibility into the design and commissioning of web products. It focuses on organisational process (policy, procurement, testing) rather than specific technical criteria.

NDC relationship: Complementary. BS 8878 tells organisations how to build accessibility into their process. NDC assesses the output of that process for neurodivergent usability. An organisation following BS 8878 could use NDC assessment as the neurodiversity-specific testing component within their accessibility programme.

PAS 6463

BSI Publicly Available Specification

What it covers: Design of the built environment for neurodivergent people. Covers physical spaces: lighting, acoustics, wayfinding, signage, and sensory environments in buildings.

NDC relationship: PAS 6463 covers physical environments. NDC covers digital products. Together they address the full spectrum of neurodivergent user experience across physical and digital spaces. There is no overlap, but the principles are aligned.

In summary: the NDC standard draws on established research and guidance including WCAG 2.2, the W3C COGA guidance, and participatory design principles. It translates this evidence into a structured, scorable assessment framework specifically for neurodivergent users. It does not compete with any existing standard. It fills the gap between them.

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