Julian G. Elliott
Scholars, teachers, clinicians, and the general public have puzzled over the nature and consequences of severe reading (decoding) problems for more than a century. With the advances of genetics, neuroscience, and psychology, we know much about the underlying nature of reading disability. However, we still have much to learn, and fierce debate continues about whether there is a subgroup of poor readers who can, or should, be called dyslexic. This issue has become highly contentious, as gaining the label can bring significant benefits in terms of resourcing, various forms of test and classroom accommodation, and more positive and understanding responses from others.
Many clinicians argue that special cognitive tests are needed to identify and diagnose those with dyslexia. These may take the form of general tests of IQ, or measures of more specific cognitive or executive functioning. Despite their popularity, the evidence for the utility of such measures is low, and many of the processes examined are often problematic for all poor readers, not merely the subgroup deemed to have dyslexia.
A further difficulty concerns intervention. There is no strong scientific support for the notion that intervention programs designed to improve underlying cognitive processes (e.g., memory processes) can successfully improve the reading accuracy of those who struggle to acquire literacy. Similarly, interventions geared to improve visual or motor functioning have not proven successful, despite often vociferous support from adherents. The only approach that has strong scientific support takes the form of an educational program that utilizes systematic, structured phonics teaching as part of a broader literacy curriculum. This finding applies equally to those who have been diagnosed as dyslexic and those poor readers who haven’t. For this reason, it is unclear how a dyslexia diagnosis helps to inform the nature of subsequent intervention.
In establishing effective forms of intervention that can cater for any child who struggles with their reading, it would appear most efficacious to utilize what is known as a “response to intervention” approach. This requires early identification of, and intervention with, all those who are making limited progress. Intervention should only utilize those approaches that have strong scientific support. The nature and extent of additional educational support should be determined on the basis of the progress that is made when additional help is given. If insufficient progress has resulted, it may well be necessary to increase and intensify the intervention. Such an approach helps to ensure that all struggling children are helped at an early stage, and no one is missed because of an absence of parental advocacy or a lack of family resource that can cover the cost of diagnostic assessment.
Literacy is a gateway to education, and yet universal literacy remains an aspiration rather than a reality. The science of reading has, however, made significant progress in understanding the key factors that impact development. Five relevant factors can be identified. The first factor is the developmental focus of models. Here the richness and dynamic nature of development is central. Models must clearly explain change and phenomena such as bi- and multilingualism. A second factor concerns bioecological influences on development. Stronger models include understandings of the complexity of gene–environment interactions in development. A third pertinent factor concerns the precise nature of the learning task facing the beginner reader, and in particular the influence of distinct orthographies. A fourth factor concerns the coherent exposition of the cognitive processes involved in “word-level” and “text-level” reading processes. Finally, contextual effects on literacy are profound. Historical and politicoeconomic forces are often linked to wide country- and region-based differences in literacy.
A detailed treatment of what is known about effective interventions for struggling readers can be built on the basis of this theorizing. Here, evidence from meta-analysis suggests that both the word-level decoding and text-level comprehension aspects of reading development can be measurably improved through evidence-based interventions. For word-level interventions studies focusing on phonics currently furnish the most secure evidence of impact. For text-level comprehension, interventions focusing on oral language development and text-based meta-cognitive strategy appear the most efficacious. Measure of treatment effects for such interventions show modest but reliable impacts on development and form the basis of ongoing efforts to optimize interventions.