The dyslexia debate and its relevance to professional practice

Dyslexia is one of the most well-known, but possibly least understood difficulties facing students. Here, Professor Julian Elliot, Principal of Collingwood College and Professor of Educational Psychology at Durham University, lays out the key ideas every teacher should know.


Sarah is a ten-year-old girl reading at the level of a typical six-year-old. She has morphed from a happy, energetic girl who used to look forward to attending school to an anxious, dispirited youngster who longs for the holidays. Her worried parents wonder whether she might be dyslexic and take her for an assessment by a reading specialist. After conducting a series of cognitive tests, parents receive confirmation that, yes, Sarah has dyslexia. The parents are overjoyed as, at last, a skilled diagnostician has seemingly finally got to grips with their daughter’s problem. At last it should now be clear how she can best be helped. And at last, Sarah should receive the resources and sympathetic understanding she requires.

Unfortunately, these beliefs are misguided and not supported by the scientific research literature. In this piece I shall try to outline the background reasons for these misunderstandings and explain why current approaches to diagnosing dyslexia are inequitable. While the dyslexia movement is largely motivated by well- meaning and committed people, their focus on a small number of struggling readers undermines the needs and potential of a greater majority with very similar – if not greater – difficulties.

An effective rhetorical device to overcome an unwelcome argument is to reframe it in such a way that it becomes easily challenged. In responding to my criticisms
about the value of the term ‘dyslexia’,(1,2,3,4,5,6) many have sought to express my position as asserting that dyslexia doesn’t exist. To refute this argument, one then only needs to point to children like Sarah and ask accusingly (and sometimes with a strong hint of irony) whether their problems and challenges should be considered as non-existent. Not only does the ‘non-existent’ argument fly in the face of what can be observed, it also would appear that the holders of such views are insensitive to the distress that such children routinely experience. In reality, the dyslexia debate(1) is not about the existence or otherwise of dyslexia but, rather, whether a dyslexia diagnosis has scientific validity. If it is not used in a clear and meaningful fashion, then the term, its operationalisation, and its consequences for professional practice are likely to be highly problematic.

Defining and diagnosing dyslexia

A key point, and one that undermines the whole dyslexia diagnosis industry, is that most leading reading scientists (and also geneticists, neuroscientists, and cognitive scientists) use the term ‘dyslexia’ as a synonym for severe difficulty with reading. (Note: here, as throughout this article, ‘poor’ or ‘struggling’ reading refers to difficulties of decoding text, not reading comprehension – although, of course, the latter is highly dependent on the former) Thus, Peterson and Pennington(7) state that:

Dyslexia is mainly defined as the low end of a normal distribution of word reading ability … Thus, in order to diagnose the disorder, a somewhat arbitrary cutoff must be set on a continuous variable. (p. 285)

Similarly, in what is widely considered to be a state-of- the-art text, Seidenberg(8) states:

Dyslexics are children (and later adults) whose reading is at the low end of a normal distribution. Reading skill results from a combination of dimensional factors (that is, ones that vary in degree), yielding a bell-shaped curve. The reading difficulties of the children in the lower tail are severe and require special attention. ‘Dyslexia’ refers to these children. Viewed this way, dyslexia is on a continuum with normal ‘reading’. All children face the same challenges in learning to read but dyslexics have more difficulty with the essential components. (pp. 156–157)

For some, dyslexia cut-off points on the reading ability continuum may be determined on the basis of administrative needs and resources:

Dyslexia is just another name for poor reading … Where you put the cut off between dyslexia and normal reading has to be agreed within your education system, your school – it could be a national policy, a policy within a local authority – there isn’t any gold standard.(9)

It is perhaps unsurprising, therefore, that the suggested prevalence of dyslexia in school-age populations can range from as low as 5% to as high as 21%. The picture is muddied not only by where on the normal distribution one would select a cut-off point but also by the unwillingness of many practitioners to view dyslexia in this way. Of course, there are some whose literacy difficulties can easily be explained by other factors (e.g. severe hearing loss or visual impairment, profound intellectual disability, or non-attendance at school alongside highly impaired home education) but these problems are highly salient and not relevant to the core issues in the dyslexia debate.

In the world of clinical practice, many do not accept dyslexia as ‘merely’ a synonym for reading disability. The widely held belief in such circles is that, presented with a struggling reader, one needs to undertake a series of cognitive tests to ascertain whether or not the person is dyslexic. This obviously implies that only some struggling readers have this condition. Immediately, and crucially, this represents a serious break between majority understandings in the scientific literature and the beliefs and practices of those who are eager to perpetuate this distinction.

So how do clinicians who hold to the notion of a dyslexic subgroup of poor readers identify which poor readers can be considered dyslexic? Certainly not by drawing upon our rapidly developing knowledge in genetics and neuroscience. While the potential of these fields for education is promising, neither can offer insights that can assist practitioners in differential assessment or intervention for those with a reading difficulty (for detailed consideration of this issue, see note 1). Of course, in addition to weak reading skills, many diagnosticians, as noted above, look for cognitive symptoms from an often lengthy list (e.g. poor phonological awareness, impaired rapid naming, inefficient and limited working memory, difficulties of attention and concentration, psychomotor weaknesses, etc). The difficulty here is that such symptoms are typically features of poor readers generally, and there is no justification for using any of these to create a bifurcated split between dyslexic and non-dyslexic poor reader groups.

Historically, another key criterion was a discrepancy between reading ability and IQ; and despite conclusive scientific refutation of the value of this distinction and recognition of this by most professional bodies, many practitioners in the UK and around the world continue to employ it. Of course, we need to give thought to the reasons why diagnosticians continue to use a procedure that has been demonstrably refuted by science yet is widely desired by the great majority of those who are seeking the assessment.

The critical question in dyslexia research is not whether dyslexic people in particular differ from ‘normal’ readers … It is whether dyslexic people differ from other poor readers.(10) (Emphasis as in the original.)

It is quite clear that there are no justifiable criteria for determining a dyslexic subgroup within a wider pool of struggling readers. Current practice, in which a dyslexia diagnosis is based on the presence of certain symptoms or features, maintains false and misleading understandings that sustain a large dyslexia assessment industry that leads to gross inequities of provision.

The relationship of a dyslexia diagnosis to intervention.

The fictional case of Sarah above reports a parental belief that a dyslexia diagnosis will point directly to appropriate, specialised intervention. Again, this represents a potentially serious misunderstanding. Here it is important to highlight the fact that there is no evidence to suggest that a dyslexic poor reader requires a form of assistance different from, or additional to, other (non- dyslexic) poor readers.

Research has clearly and conclusively demonstrated that non-educational approaches often vaunted for those diagnosed as dyslexic (e.g. brain training, audiological processing training, visual therapies of various kinds, and psychomotor programmes) do not have scientific support and should not be utilised. The only form of intervention, to date, that appears effective for struggling decoders is that which utilises systematic and highly structured phonics teaching within a broader range of literacy activities. Interestingly, even those who are eager to maintain the use of dyslexia assessments and diagnoses will rarely take issue with the assertion that there is no special treatment for dyslexic individuals that is not equally valuable for other struggling readers. Yet, in the dealings of some practitioners with teachers and families, such a distinction is often implied.

Inequities of provision

Perhaps the most passionate argument put forward by the proponents of dyslexia diagnosis is that this can prove highly valuable to the individual concerned. Let us ignore, for the moment, the conceptual and scientific flaws in the diagnostic process, and consider the issue of benefit independently. According to proponents, a diagnosis of dyslexia can bring succour to the individual and their family, greater understanding, sympathy and patience from school staff and peers, modifications and adjustments to academic demands (including examination procedures) and, in some cases, extra resources in the form of equipment or special tuition/schooling.

Many dyslexic individuals state that, prior to their diagnosis, they had considered themselves to be stupid, or were frustrated that others had thought this of them, or that they were lazy – clearly, the diagnosis can have the effect of reducing negative, pejorative attributions that can help the struggling reader and their families. The difficulty is that if it takes a dyslexia diagnosis to effect positive outcomes of this kind, what are the implications for the many thousands of struggling readers who do not receive this label? Is it not likely that, in a zero-sum game, the ‘non-dyslexic’ poor readers are more likely to be seen in a negative light? Will this latter group be considered to comprise those of questionable intellectual ability, those who are not prepared to work, or the offspring of feckless, uncaring parents with no regard for learning?

Of course, such a distinction is wholly fatuous. In actuality the dyslexia label is most likely to be applied, not to more worthy, or more unfortunate, individuals, but rather to those whose families have the drive – and, in many cases, the financial means – to gain access to a diagnostician. Rarely, it seems, will a struggling reader fail to receive the dyslexia label if a private consultation has been undertaken. However, it is one thing to use one’s private resources to gain a diagnosis; it is quite another to then expect others to pay the costs of additional educational inputs that are contingent upon this. Thus, the parents of diagnosed children sometimes seek funding from local authorities for their children to access specialist independent schooling. Some who are refused this subsequently apply to have their child’s case heard by an SEN tribunal. The fact that there may be many thousands of children with far greater literacy difficulties in the local area does not necessarily deter tribunals from ruling against local authorities and mandating the expenditure requested. To avoid the costs of defending their position and any negative publicity that results, local councils sometimes give in to parental requests and provide often substantial funding without the case going to the tribunal hearing. Of course, one has sympathy for desperate parents, but the costs of these isolated cases reduce the wider support that can be offered to large numbers of other children.

Concluding remarks

What we need are education systems that are able to identify and intervene with all struggling readers as early as possible. The nature and level of support provided should be a function of the response that the child demonstrates as a consequence of intervention. Additional resources are applied where earlier forms of intervention appear insufficiently powerful. With such an approach, known in the special education field as response to intervention, there is no need for a dyslexia diagnosis or the deployment of the wait-to-fail model upon which these are typically based.

Of course, where there are finite resources, there will typically be winners and losers. Currently, the winners are those who can acquire a dyslexia diagnosis and gain the various benefits that proponents cite to justify the continuance of this approach. The losers are the other struggling readers, often already disadvantaged in other aspects of their lives, for whom the perceived benefits of any such diagnosis are not forthcoming. The dyslexia assessment industry sucks up resources and reduces the opportunity for school systems to operate more equitable and effective response to intervention models. It also reduces pressure upon the state to recognise and address the needs of huge numbers of children whose poor reading skills impede their life chances. We need to address this problem as a matter of some urgency. While frequently criticised for my stance, I make no apologies for attacking the use of dyslexia diagnoses on conceptual, scientific, social and ethical grounds.


1. Elliott, J. G. and Grigorenko, E. L. (2014a) The dyslexia debate. New York, NY: Cambridge University Press.
2. Elliott, J. G. and Grigorenko, E. L. (2014b) ‘The dyslexia debate’, The Psychologist 27 (8) pp. 576–580.
3. Elliott, J. G. (2015a) ‘The dyslexia debate: actions, reactions, and over-reactions’, Psychology of Education Review 39 (1) pp. 6–16
4. Elliott, J. G. (2015b) ‘The author’s response to peer commentary’, Psychology of Education Review 39 (1) pp. 35–36.
5. Elliott, J. G. and Resing, W. C. M. (2015) ‘Can intelligence testing inform educational intervention for children with reading disability?’, Journal of Intelligence 3 (4) pp. 137–157.
6. Elliott, J. G. and Nicholson, R. (2016) Dyslexia: developing the debate. London: Bloomsbury Press.
7. Peterson, R. L. and Pennington, B. F. (2015) ‘Developmental dyslexia’, Annual Review of Clinical Psychology 11 (1) pp. 283–307.
8. Seidenberg, M. (2017) Language at the speed of sight: how we read, why so many can’t, and what can be done about it. New York, NY: Basic Books.
9. Snowling, M. J. (2013) Dyslexia: an impairment of language learning. British Psychological Society/British Academy Lecture. (Reported in The Psychologist 26, pp. 786–795).
10. Rice, M. and Brooks, G. (2004) Developmental dyslexia in adults: a research review. London: National Research and Development Centre for Adult Literacy and Numeracy, UCL Institute of Education.