3.5 New definition of dyslexia by the SASC (2024)

By the beginning of the new millennium, dyslexia had transitioned from a condition once shrouded in scepticism and relative obscurity to one of the most diagnosed learning difficulties in childhood, with many institutions seeking to provide increasingly more standardised and comprehensive definitions. Therefore, the SASC (SpLD Assessment Standards Committee) announced a new definition of dyslexia in 2024 as follows:

• Dyslexia is primarily a set of processing difficulties that affect the acquisition of reading and spelling.
• In dyslexia, some or all aspects of literacy attainment are weak in relation to age, standard teaching and instruction, and level of other attainments.
• Across languages and age groups, difficulties in reading and spelling fluency are a key marker of dyslexia.
• The nature and developmental trajectory of dyslexia depends on multiple genetic and environmental influences.
• Dyslexic difficulties exist on a continuum and can be experienced to various degrees of severity.
• Dyslexia can affect the acquisition of other skills, such as mathematics, reading comprehension or learning another language.
• 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, orthographic skills and processing speed problems can contribute to the impact of dyslexia and therefore should be assessed.
• Dyslexia frequently co-occurs with one or more other developmental difficulty, including developmental language disorder, dyscalculia, ADHD, and developmental coordination disorder.

The definition highlights that dyslexia is primarily about processing difficulties impacting reading and spelling skills. It acknowledges that these difficulties can vary in severity and can affect different aspects of literacy. The definition also emphasises that these challenges are not reflective of a person’s overall abilities but are specific to their literacy skills in relation to their age and the standard teaching they have received.

In preparing the definition, the authors did empirical research and thus noted several points that scored highly or in agreement. From these, one can agree on the following:

• ‘Dyslexia is primarily a set of processing difficulties that affect aspects of literacy attainment, despite the educational opportunity to learn to read and spell.’
• ‘Discrepancies between intellectual ability and literacy attainment is useful indicator of a specific learning difficulty but is not sufficient for a diagnosis in and of itself.’

While we embrace this new definition, it’s crucial to remember that our ultimate responsibility – regardless of our personal agreement or disagreement – is to provide support to those in need.