The identification of dyslexia has a long and contentious history. Opinions on it vary, with some claiming that dyslexia does not exist and others arguing that it is under-diagnosed and far more prevalent than current estimates. Some local authorities advise against the identification of dyslexia at all.

Scotland has its dyslexia assessment process but there is no clear universal pathway for the assessment of children with difficulties such as dyslexia in England, Wales and Northern Ireland. The systems for the identification of learning needs, assessment and intervention strategies vary hugely from area to area; Hutchinson (2021) described it as a postcode lottery.

The most recent attempt at a working definition for dyslexia came from the Rose Review in 2009.

Dyslexia and the Rose review

This review provided a definition of dyslexia (see below) and argued for an increased role for specialist teachers in supporting and identifying dyslexia, but this did not lead to the hoped-for rise in support for dyslexic students. While funding for specialist teachers was implemented, the funding was not renewed following an initial period and a change in government administration.

The Rose definition significantly influenced practice for children with specific learning difficulties but has gradually gathered criticism and has not been universally accepted. In the 15 years since, research about the causes of dyslexia has developed.

Research on dyslexia

We now understand dyslexia to be one of a set of overlapping developmental disorders, rather than a specific learning difficulty that should be diagnosed in isolation.

Indeed, the current concept of dyslexia is that it is the outcome of multiple genetic and environmental causes, and it is frequently seen in combination with other disorders that affect learning, particularly developmental language disorder (DLD) and attention disorders, such as ADHD.

Given the above - amid the well-publicised crisis in support for special educational needs and disabilities (SEND), budget cuts and the fragmentation of specialist support in schools - there is a high level of confusion about how dyslexia should be identified and supported in the UK.

Defining dyslexia

We actually now know a great deal about what dyslexia is.

One important development is a recognition of the complex and variable factors that influence reading and spelling delays and difficulties.

Take the example of two children in Year 4, both of whom are reading well below age-level expectation.

One has received supplementary support via a catch-up programme and one-to-one individualised teaching but still has problems decoding text. The other is a child who has recently arrived in the UK and is new to English.

The first shows a persistent reading difficulty despite high-quality intervention, and can be described as “dyslexic”. The second may have dyslexia but this is unlikely - rather more likely is that they will catch up as their English improves and they receive support in learning to read in English.

Reading difficulties

Another example might be two children in Year 6 at primary school.

One has recently joined the school, his third new school in three years, and his attendance is poor. He can decode basic text but does not enjoy reading, and loses interest very quickly in any literacy-based activities. His oral language is weak. It has been difficult for his current teachers to get a sense of his support needs and they are exploring how best to arrange assessment and reading intervention.

The second child reads very slowly, makes very frequent spelling errors and has difficulty reading her own writing. She has had some additional support when resources have allowed. At home she loves stories and being read to, and her oral vocabulary is extensive. She enjoys discussing what she is reading and her enthusiasm for learning in other areas of the curriculum has led her teachers to believe she will eventually catch up with reading.

Both children could be dyslexic (the first may have additional developmental language difficulties), but both require further assessment to explore the impact of underlying difficulties that are making learning to read more difficult than expected for their age. They then need appropriate, well-evidenced interventions.

Interventions for dyslexia

We also know a good deal more about how to support children and ameliorate the challenges of dyslexia in the early years of school.

Intervention can be an important way of preventing the impact of dyslexia risk. In the early years it is best to follow a tiered approach, initially checking that a child at risk is keeping up and, if not, putting in place catch-up support to help them get to grips with the alphabetic principle - that is, teaching them letters and sounds and how to link them in blending words.

If progress is slow then additional, individualised instruction is required.

It is important, however, to appreciate that different kinds of risk need different interventions.

Role of oral language

Children who come to school with poor oral language are at high risk of reading difficulties; they will require support with language as well as with the first steps into literacy.

In contrast, some children have good spoken language but more specific difficulties learning letter-sound correspondences and how to use them; in particular, phoneme awareness.

So we should not be leaving assessment and intervention to chance.

Yet parents and teachers are often unsure whether they should refer a child for assessment for dyslexia or another difficulty that is affecting learning to read. They may not be certain of when and how to do this.

Reaching agreement

To address these concerns, researchers Julia Carroll, Caroline Holden and Maggie Snowling decided to carry out a particular form of research called a Delphi study with the aim of bringing experts in dyslexia together to reach an agreed definition and pathway of support.

They recruited an international, multi-disciplinary panel of experts in dyslexia with different professional backgrounds, including researchers, psychologists, speech and language therapists, specialist assessors and teachers working with both children and adults, as well as individuals with personal experience of dyslexia.

After starting with a set of 55 statements, the panel finally demonstrated a high level of agreement for 42 statements about the nature and identification of dyslexia. Those statements have been used to frame an updated definition of dyslexia and guidance for support and assessment.

Below we share the outcomes of the study.

What is dyslexia?

The expert panellists agreed that dyslexia is a set of processing difficulties that affect the acquisition of reading and spelling. The most commonly observed processing difficulty is a phonological deficit, but this is not the only difficulty that is relevant. Experts agreed that accounts of dyslexia that attribute it to a single cause, such as a phonological deficit, do not account for individual variability or the highly overlapping nature of dyslexia with other disorders. In the longer term, a difficulty in reading fluency is a key marker of dyslexia.

Assessing all these difficulties and their impact on academic attainment is an important part of assessing whether a child has dyslexia.

Warning signs for dyslexia

There are warning signs that we should be aware of, such as a history of reading difficulties in the family, previous support from a speech-language therapist or ongoing language difficulties. It is clear that schools need to put support in place for children who are finding it hard to learn letter sounds, letter names and how the reading process works.

A slow start in reading, effortful learning and reading that lacks fluency can all be indicators of a reading difficulty. Once a child starts to refuse to engage with reading activities then alarm bells should be ringing.

Classically, dyslexic children have been thought of as having high intellectual attainment alongside poor literacy, but we now have agreement that dyslexia occurs across the range of intellectual attainment.

While we should not be searching for a discrepancy between intellectual attainments and literacy skills as a defining characteristic of dyslexia, comparative and unexpected weaknesses in literacy attainment compared with other areas of attainment can add to the evidence that supports identification. These discrepancies should be recognised as a potential source of frustration for the individual concerned.

How a child responds to support can be a good indicator of whether they should be considered dyslexic. This is because many individuals who show literacy difficulties will actually respond well to high-quality targeted tuition and not show long-term problems. Individuals with dyslexia, on the other hand, will have long-term difficulties into adulthood, though the nature of those difficulties changes.

Where are we now with dyslexia?

Unlike in other European countries, there is no universal structure in England, Wales or Northern Ireland for identifying and supporting pupils with dyslexia. Germany, in contrast, has developed guidelines for both the diagnosis and treatment of reading and/or spelling disorders, and these are updated regularly.

In the UK, the Scottish government does have a dyslexia identification pathway. The three-phase process suggested in this pathway has significant similarities to the process we suggest below, though monitoring response to intervention is not explicitly mentioned.

Once identified, school students are most likely to receive intervention and support from teaching assistants, who are much less likely to have specialist training in evidence-based interventions.

The panellists involved in the Delphi study were keen that the identification process should not be used as a way of denying support to some children. Not every child with literacy difficulties has dyslexia, but every child with literacy difficulties should be supported appropriately.

In the earliest years of primary school, support is more important than identification, and support should depend on need rather than the underlying cause of the difficulty.

What should the process of identification be?

The findings of the Delphi study suggest that we need a national statutory pathway to dyslexia assessment. A four-stage model would clarify the processes and help to ensure that children are identified before they get to Year 6.

Stage 1
This would involve considering or ruling out other factors that might be the primary reason for the child’s difficulties in accessing the teaching in the classroom; for example, the need for additional support for English as an additional language, referral for a sight/hearing test, etc. Crucially, additional support should be given to all children with difficulties in developing oral language (speaking and listening), picking up phonics, understanding texts and learning how to write.

Stage 2
This is an information-gathering stage (for example, via screening and parent questionnaires), followed by immediate planned intervention. This should happen in a timely manner, before the end of key stage 1, as ages 5-9 are the key years for literacy acquisition. It is important to assess the child’s ability to hear and manipulate sounds in speech (phonological awareness), what they know about letters, sounds and words, and what they know about reading.

Examples of screeners include the Reading Screen, developed by OxEd, although many screeners available for schools have not yet been extensively reviewed and evaluated. Some organisations such as the Helen Arkell Dyslexia Charity are working to put together a small battery of tests that could provide a “first look” at children at risk of reading difficulty.

Similarly, researchers at Aston University, in collaboration with Wiltshire Council Specialist SEN Service, are developing a proposal to implement a universal screener at KS1. The screener, developed by researchers Joel Talcott, Susan Gathercole and Jo Van Herwegen, looks at a child’s level of language, phonological processing, working memory and sustained attention.

When emerging difficulties are identified and addressed early, there is great potential for avoiding persistent and entrenched difficulties later. The current inequality of access to quality resources and guidance to support children’s identified needs highlights the urgency for innovative responses that enable inclusive and equitable education in a pragmatic and affordable way.

Stage 3
This is a stage of observing how the child responds to intervention. This stage should therefore be relatively short, perhaps no longer than 6 to 12 months.

At this point, there are two potential outcomes for the child.

The first potential outcome is that the child makes rapid progress - much better progress than previously - and is in a better position to access teaching in the classroom with their peers. It is clear they are vulnerable but with the right level of support and intervention, they make good progress.

The second potential outcome is that the child does not make the same level of progress. They may make slow, hesitant or no progress. It is clear that they are experiencing persistent difficulties and the school should now without delay move to Stage 4.

Successful intervention for children having difficulties in KS1 and early into KS2 might include a daily 20-minute session, delivered by a trained teaching assistant, over 20 weeks, focusing on building the children’s knowledge of phonemes, how phonemes link to letters and word and text reading. A study by Peter Hatcher and colleagues in 2005 found that children involved in small-group teaching following this model made considerable progress.

Stage 4
If a child does not respond to the intervention teaching, it is time to look for further external support. This is the crucial point where, currently, many children slip through the net. For children who are experiencing persistent difficulties in literacy learning, there should be a state-funded referral process for a more comprehensive diagnostic assessment. Schools should be able to refer children for further assessment and ongoing support.

This assessment process should be carried out by a specialist teacher or psychologist, using standardised assessments and approved reporting formats (see the SASC website).

From this point, sustained and appropriate interventions and resources can be put in place. Establishing the process of assessment and intervention needs to become a priority if we are serious about working to ensure that all pupils learn to read.

There will likely remain a small proportion of children who, despite assessment and intervention, continue to experience a range of persistent and more severe literacy difficulties and underlying cognitive difficulties. Dyslexia cannot be cured, but its ongoing impact can be ameliorated with the use of assistive technologies and ongoing support for reading and spelling.

Many of these children may have broader language or other difficulties. For these children, before transition to secondary school, there should be another review and referral point, ideally between the ages of 9 and 11, with an emphasis on clear communication of support needs at the point of transition.

In conclusion, dyslexia is a persistent, long-lasting difficulty that may be helped with intervention, but the impact remains significant for many. If we are serious as a nation about ensuring that all students receive the very best education possible, we need to address the gap in provision. The phonics screening check is a natural first step. But there is plenty more to be done.

Julia Carroll is professor of psychology in education at the University of Birmingham; Dr Megan Dixon is a doctoral student and associate lecturer at Sheffield Hallam University; Maggie Snowling is emeritus research fellow in psychology at St John’s College, University of Oxford. Caroline Holden is a specialist teacher-assessor with over 44 years’ experience working across primary, secondary, further and tertiary education. She was vice-chair of the SpLD Assessment Standards Committee 2017-2024,