The New Dyslexia Diagnostic Criteria- What It Means for Families and Schools

The landscape of dyslexia diagnosis in the UK is evolving. In May 2024, the SpLD Assessment Standards Committee (SASC) released a briefing paper summarising findings from the Delphi Dyslexia Study, which proposed a new definition of dyslexia. Soon after, on 16 May 2024, the British Dyslexia Association (BDA) announced that it had adopted this proposed definition, marking a pivotal shift in how dyslexia is understood and diagnosed in the UK.

This new approach moves away from the old “IQ-achievement discrepancy” model,  which compared a child’s intelligence score with their reading ability and instead focuses on how literacy difficulties affect day-to-day learning. The change reflects years of research calling for a more inclusive and functional understanding of dyslexia.

The New Definition (Delphi Study, 2024)
“Dyslexia is a set of processing difficulties that affect the acquisition of reading and spelling. The most commonly observed cognitive impairment in dyslexia is a difficulty in phonological processing (i.e. in phonological awareness, phonological processing speed or phonological memory). However, phonological difficulties do not fully explain the variability that is observed. Working memory, processing speed and orthographic skills can contribute to the impact of dyslexia.”

- SpLD Assessment Standards Committee (SASC), May 2024
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This definition, created through collaboration between UK dyslexia experts, researchers, and Educational Psychologists, represents a research-driven and consensus-based understanding of dyslexia as a spectrum of difficulties rather than a single condition.

What’s Changing and Why It Matters

In the past, dyslexia was often identified through the “discrepancy model,” which relied on finding a gap between a child’s IQ and their literacy performance. This approach left many bright children unsupported because their general intelligence compensated for literacy struggles or conversely, excluded children whose IQ scores didn’t meet a certain threshold.
Under the new definition, dyslexia is recognised as a continuum of cognitive processing challenges, with key emphasis on:

• Phonological awareness (understanding how sounds relate to letters)
  
  
• Working memory and processing speed
  
  
• Orthographic skills (recognising written word patterns)
  
  
  

This framework supports earlier identification, broader access to help, and removes barriers that previously delayed intervention.

What the 2025 Criteria Mean for Parents and Schools
The 2025 diagnostic standards bring a number of important implications for families, schools, and allied professionals:

1. Earlier intervention becomes the norm: Schools are encouraged to support children with literacy difficulties before a diagnosis is confirmed.
   
   
   
2. Assessment becomes more holistic: Reports will focus on strengths, weaknesses, and real-world learning impact, not just standardised test scores.
   
   
   
3. Collaboration is key: Speech and language therapists, SENCOs, and Educational Psychologists are expected to work together on intervention planning.
   
   
   
4. Language takes centre stage: Many literacy difficulties have underlying roots in language processing, sound awareness, and comprehension- areas central to speech and language therapy.

At Write2Talk, we understand that dyslexia is more than just difficulty with reading, it’s often tied to underlying language and processing challenges that affect confidence and classroom participation.
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Our therapy sessions focus on:

• Phonological awareness: Strengthening the ability to hear, identify, and manipulate sounds in words.
• Auditory and working memory: Improving retention and sequencing of spoken information.
• Vocabulary and comprehension: Expanding understanding and expressive language.
• Narrative skills: Helping children organise ideas logically, a key skill for both speaking and writing.
  
  
  

We also collaborate with educators to design integrated literacy support plans aligned with the new SASC guidelines, ensuring children receive consistent help across school and home settings.