Is “Dyslexia” a Useful Label for Diagnostic and Treatment Purposes?

Last year I administered a comprehensive language and literacy reassessment to a bright 12-year adolescent with persistent reading deficits. When asked to discuss self, he readily offered, ‘I am dyslexic’, when describing some of his self attributes. This took me by surprise a few weeks later, as testing was way underway and I had the opportunity to create a comprehensive profile of his strengths and needs. This student did not present with phonological deficits (a hallmark symptom of dyslexia as per IDA as well as numerous research studies). The student indeed presented with clear reading-related deficits characterized by impaired reading fluency, nonword reading, and abstract reading comprehension abilities (as well as spelling and writing deficits of non-phonological nature). But he also presented with other deficits which were impacting his ability to read. They were much broader and included verbal reasoning and pragmatic deficits which were affecting his comprehension of read text.

However, prior to my reassessment, the above deficits were not identified on the previous testing for this student. Indeed, a year prior he underwent a comprehensive psychological assessment and was diagnosed with dyslexia. The trouble was that the recommended “treatment” options, as well as accommodations and modifications, did not positively affect this student’s intervention even one bit. They were simply too general and nonspecific and did not result in targeted remediation goals. In contrast, after my reassessment revealed specific deficits areas and resulted in specific treatment goals in affected areas, the treating therapist (recommended by myself to the parents) was able to make a seemingly remarkable process in a relatively short period of time for this student.

This student’s story is not a standalone case by far. In my clinical practice as a comprehensive independent language literacy evaluator, I routinely perform comprehensive assessments for students previously diagnosed with dyslexia, who are making minimal treatment gains in intervention. In all the cases so far, the problem was that beyond being diagnosed with this label, the evaluators did not create meaningful treatment plans for the students in question, and instead made broad recommendations for the use of specific reading programs or mere accommodations and modifications, which were often completely inapplicable to the students’ deficits.

So why is the “dyslexia” label, beloved by parents and advocates alike, so problematic and controversial for diagnostic and treatment purposes? For starters, it is often defined very differently in various studies (Elliot & Grigorenko, 2014). Some researchers define it as a struggle with phonemic awareness, others as a struggle with fluent single word decoding. Still, others define it as decoding difficulties that cannot be explained in an alternative fashion (not due to something else). It has been defined as a significant reading performance between reading and IQ, as phonological or RAN/RAS deficits, as failure to make meaningful progress in reading even after evidenced-based reading instruction, with many other definitions not even being mentioned here.

Then there’s the belief of parents and professionals in the unsubstantiated “dyslexia subtypes” (e.g., phonological, surface, double deficit, etc.) debunked by research studies (Manis, Seidenberg, Doi, McBride-Chang, & Petersen, 1996; Manis et al., 1999; Stanovich, Siegel, & Gottardo, 1997; Rack, Snowling, & Olson, 1992; Van den Broeck & Geudens, 2012, Tamboer et al, 2014; Zoubrinetzky et al, 2014). That belief is so prevalent that some reading tests such as the Feifer Assessment of Reading (FAR) actually purport to help determine an individual’s specific subtype of reading impairment. The problem is that the number of symptoms of dyslexia described in the literature exceeds the number of subtypes, and their underlying relations remain unclear (Tamboer, Vorst, & Oort, 2016; Kornilov, & Grigorenko, 2018)

This artificial divide of poor readers into dyslexic and non-dyslexic groups lacks scientific rationale (Elliot & Grigorenko, 2014). There are neuroimaging data that point to both structural and functional differences in the brains of children and adults with reading deficits on reading tasks compared to typically developing peers. The functional differences include under activation of the left occipitotemporal cortex and the left temporoparietal cortex and heightened activation in parts of the left interior frontal cortex. The structural differences, include reduced grey matter and decreased white matter connections (D’Mello & Gabrieli, 2018). However, no such functional and structural neuroimaging data exist for subjects artificially classified as dyslexic vs. non-dyslexic poor readers.

Then there’s the continued prevalence of the outdated support for the Single Deficit Model of Dyslexia, which supports an “all or none” position (one either has dyslexia or doesn’t), which assumes that dyslexia has a single biological (genetic/neurological) and a single cognitive causal basis (Muter, 2021). It is depicted as a specific deficit “residing within the phonological system of the language network that results in difficulty with learning to decode and spell printed words while sparing other language functions such as semantics, syntax, and pragmatics (e.g., Schatschneider & Torgesen, 2004; Stanovich, 1988)” (Compton, 2021, p. 225).

However, “current models of dyslexia indicate that single deficit models are inadequate to account for the variability found in dyslexia (e.g., Pennington et al., 2012; Perry et al., 2019)”. The new models emphasize a multifactorial approach to etiology with primary involvement of phonological processing deficits as well as weaknesses in other oral language skills, processing speed, and possibly executive function (Petersen & Pennington, 2015). The upshot is that not all individuals with dyslexia have the same underlying deficits that consistently lead to problems in learning to read and spell (Catts et al., 2017; Catts & Petscher, 2020; Snowling, 2008). Furthermore, there’s growing evidence that dyslexia frequently co-occurs with other disorders such as attention-deficit hyperactivity disorder (ADHD) (Boada et al., 2012; Willcutt & Pennington, 2000), math deficits (e.g., Landerl & Moll, 2010), and various language-based deficits such as specific language impairment (e.g., Bishop & Snowling, 2004; Snowling & Melby-Lervåg, 2016) (Compton, 2021, p. 225).

Indeed, given the disparity in definitions (only a few of which were mentioned in this post) it is not surprising that studies have found that not only do the various “dyslexia” assessors assess dyslexia differently, they also lack consistency and reliability with respect to assessment procedures, interpretation of literacy deficits, view of discrepancy models, as well as standardized and clinical testing practices, with many of the assessors over-relying on professional observation and experience above testing results (Ryder & Norwich 2018, Harrison & Holmes, 2012; Proctor & Prevatt, 2003; Sparks & Lovett, 2009; Watkins, Glutting, & Youngstrom, 2005). As a consequence, of these faulty practices, the term “dyslexia” does not functionally contribute to the understanding of what deficits the student is experiencing in the areas of literacy (Elliot & Grigorenko, 2014)

So what can assessors functionally do for the “dyslexic” or merely “struggling to read” students during the assessment process? For starters, regardless of assigned labels, they need to comprehensively assess all areas of language and literacy relevant to the acquisition of reading (and writing abilities), in order to create a profile of the students’ strengths and needs. Below are just a few essential components involved in skilled reading:

• Phonological and Phonemic Awareness Skills
  • Phonological awareness assessment/intervention has predictive power until 2nd grade. After that it does not add information to the prediction of 4th-grade reading abilities (Hogan, Catts, & Little, 2005) unless the student continues to present with significant reading challenges as evident via sound blending deficits (Kilpatrick, 2012)
• Orthographic Mapping Abilities
  • Formation of letter-sound connections to bond the spellings, pronunciations, and meanings of specific words in memory
  • Explains how children learn to read words by sight, to spell words from memory, and to acquire vocabulary words from print
    • Enabled by phonemic awareness and grapheme-phoneme knowledge (Ehri, 2014)
• Semantic Knowledge
  • Vocabulary manipulation
• Morphological Knowledge
  •  Knowledge and manipulation of affixes
• Rapid Naming Abilities
  • Rapid automatized naming (RAN) and not phonological awareness has been found to be a consistent predictor of reading fluency in all orthographies (Landerl, et al, 2019).
    • Poor rapid automatized naming abilities (on alphanumeric and nonalphanumeric tasks) have been found to be a long-term and universal symptom of reading deficits (Araújo & Faísca, 2019)  
• Reading Fluency
  • Rate
  • Accuracy
  • Prosody
• Reading Comprehension
  • Gestalt processing
  • Background knowledge
  • Inference making  
  • Grasp of text structure
  • Grasp of literary devices

We need to assess students in all of the above areas, as well as in the following areas of language related to literacy competence.

1. Phonology (understanding and use of speech sounds -phonemes)
2. Morphology (understanding and use of word parts including morphemes, affixes, etc.)
3. Vocabulary and Semantics (understanding how to define and manipulate words)
4. Syntax (understanding and use of complex sentence structures)
5. Pragmatics (understanding and use of language in social contexts)

There are a number of assessment tasks sensitive to language and literacy impairment identification. These include but are not limited to following directions, nonword repetition, phonemic awareness, orthographic knowledge, nonword reading, rapid naming, etc. In the absence of strong assessment comprehensive assessment instruments such as the Test of Integrated Language and Literacy (TILLS), evaluators can effectively use these tasks in order to assess the students’ language and literacy abilities. However, even with access to strong standardized tools, evaluators need to administer several clinical assessment tasks strongly associated with academic success. These are:

1. Narrative/discourse assessment (task selection is age dependant)
2. Pragmatic language assessment
3. Reading assessment
   1. Elementary
   2. Adolescent
4. Writing assessment
   1. Elementary
   2. Adolescent

Given the multitude of skills involved in learning to read in the areas of both language and literacy, it is imperative that no literacy interventions be provided until a targeted assessment takes place. Evidenced-based assessments focus on uncovering deficit areas. Hence, the administration of general language or academic tests will not be sufficient. Rather assessments need to targeted reported deficits, which can be selected via the use of relevant checklists distributed to both parents and professionals. Assessment should be a mandatory prerequisite to effective and evidenced-based goal formulation for treatment purposes. As such, goal target selection should never be performed on a random basis, but rather prioritized based on the results of the student’s comprehensive assessment. As such, instead of merely diagnosing the student with dyslexia and making random treatment recommendations the following report format will be far more useful.

•Impressions – is a section that provides a narrative review of a child’s language and literacy weaknesses which includes subjective ratings of deficits (below average, severely impaired, profoundly impaired) based on the combination of standardized & clinical assessments.

•Comprehensive language and literacy assessment revealed that the student presents with previously unidentified language and literacy deficits which are presently adversely affecting his educational performance and require targeted remediation.  These deficits include below average-moderately impaired metalinguistic comprehension and oral language, severely impaired pragmatic abilities as well as below-average reading, and writing abilities, which require targeted intervention services.

•Student’s oral expression and metalinguistic weaknesses are characterized by impaired ability to explain ambiguous and figurative language as well as engage in age-level discourse. 

•Student’s pragmatic deficits are characterized by impaired ability to engage in social routine language, interpret context clues, comprehend irony and sarcasm, as well as express non-verbal body language and context clues.

•Student’s reading deficits are characterized by below-average phonemic awareness, reading accuracy, and reading comprehension abilities. Additional deficits further impacting students’ reading comprehension include impaired oral language, literate vocabulary knowledge, background knowledge, gestalt processing, and verbal reasoning abilities. 

•Student’s spelling deficits are characterized by significant weaknesses in the areas of Phonemic and Morphological Awareness.  Please find the detailed SPELL-2 assessment results and recommendations summary in Appendix A of this report.  

•Student’s writing deficits are characterized by weaknesses in the areas of spelling, logical sentence construction, sentence revision, persuasive composition development, as well as proofreading and editing. 

But the above is still not enough. The assessor needs to provide suggested long and term goals for the intervening practitioners in order to effectively target areas. Here are some examples of specific pragmatic as well phonics goals:

Long Term Goals: The student will improve his pragmatic abilities in order to effectively communicate with a variety of listeners/speakers in all social and academic contexts

Short Term Goals

1. Student will effectively interpret facial expressions, body language, and gestures by stating visual clues which assisted him in the making of this determination.
2. Student will recognize sarcastic and ironic comments and infer what someone else is thinking in presented scenarios   
3. Student will appropriately interpret  tone of voice and prosody of others in the presented scenarios 

Long Term Goals: Student will improve phonics abilities for reading purposes

Short Term Goals:

1. Student will map vowel combinations to represent a single vowel sound (e.g., ee, ea, ie can represent /ē/)
2. Student will map consonant trigraphs (e.g., tch for /ch/, dge for /j/, etc.)
3. Student will map consonant clusters/blends with 2 sounds in beginnings of words (e.g., /st/, /qu/, /sc/, etc.)
4. Student will map consonant clusters/blends with 3 sounds in beginnings of words (e.g., /str/, /spl/, etc.)
5. Student will map consonant clusters/blends with 2 sounds at the end of words (e.g., /mp/, /nd/, /ft/, etc.)
6. Student will map silent letter patterns (e.g., kn for /k/, mb for /m/, etc.)

So what are some takeaways I am hoping for from this post?

It’s important for the readers to understand that the term “dyslexia” remains a very misunderstood and misinterpreted label which does not meaningfully inform intervention. Effective interventions are not based on labels but on the results of psychometrically strong assessments which have uncovered specific literacy-related deficit areas. Specialized programs are not necessary for successful intervention purposes and should never be used without assessment findings. Evidence-based intervention should focus on specific student-related treatment goals and objectives instead of being selected from a pre-packaged step-by-step program/approach. Treatment of reading and writing will involve concomitant treatment of oral language as well as pragmatic deficits. Comprehensive language and literacy assessments should be a mandatory prerequisite to any literacy-related intervention services!

Useful Reading Related Links:

1. Clinical Assessment of Reading Abilities of Elementary Aged Children
2. Adolescent Assessments in Action: Clinical Reading Evaluation
3. The Role of Speech Language Pathologists (SLPs) in Assessment and Management of Dyslexia
4. Comprehending Reading Comprehension
5. Language and Literacy Assessment Tasks and What They Measure
6. Comprehensive Assessment of Elementary Aged Children with Subtle Language and Literacy Deficits
7. The Role of Pragmatic Language in Reading Comprehension and Written Expression: Focus on Assessment

Free Webinars:

1. How Language Affects Reading: Free Webinar for Parents and Professionals
2. Neuropsychological or Language/Literacy: Which Assessment is Right for My Child?

 Continuing Education:

1. Emergent Reading Master Course
2. Reading Fluency and Reading Comprehension Master Course
3. The Science of Reading Literacy Certificate for SLPs

Select References:

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