If one does not measure the student’s cognitive (perceptual) strengths and weaknesses, and determine an estimate of IQ or overall cognitive ability, one misses a large amount of extremely helpful information regarding the student’s strengths and weaknesses, skills and abilities, and expected level of performance.

This is why, at Cumberland Education, we believe that a comprehensive assessment of literacy skills, cognitive (perceptual) skills, in addition to forming an estimate of a student’s learning potential, is essential for understanding student’s difficulties in learning generally, and difficulties such as Dyslexia more specifically.

There has been a relatively recent change in Australia regarding the way some professionals diagnose and treat students who experience difficulties in learning. Specifically this trend has focussed on the identification and the provision of services for one such condition- Dyslexia.

This trend has meant that some professionals have moved away from measuring and evaluating intelligence (IQ) or cognitive ability in students who experience Dyslexia, and instead, now focus on just measuring the core deficits in areas associated with reading and writing difficulties such as phonological processing, rapid automatic naming, and orthographic processing. As will be explained later in this paper, such skills may, or may not, be classified as subtests of IQ.

It is the author’s belief that this recent trend, comes at a cost to many individuals with learning difficulties more broadly, and Dyslexia more specifically. The aim of this discussion paper is to outline the nature of this changing trend in education, and the costs to many of our students.

Ultimately, it is the author’s aim to convey the importance of IQ assessment in the identification and treatment of all learning difficulties (LD), including dyslexia.

Firstly, what is an Intelligence Quotient (IQ)?

Cognitive theorists claim that intelligence can be measured and reported in the form of an Intelligence Quotient (IQ) or a score that represents cognitive performance in various aspects of intelligence. There are various theorists who provide different models for how to conceptualise intelligence. For example, the Wechsler theorists, who are responsible for the WISC-V test of intelligence, conceptualise IQ as being composed of 5 areas of cognitive ability, which then combine to form a Full Scale (overall) IQ score. A differing model of intelligence is the Cattell-Horn-Carroll (CHC) theory, which forms the theoretical basis for the Woodcock Johnson tests of intelligence. This model conceptualises intelligence as being composed of at least 8 different broad abilities (factors of intelligence), over 70 narrow abilities, as well as one overall general intelligence measure.

Secondly, what is Dyslexia?

This is a vexed question. Since its initial conceptual development, the definition of Dyslexia has been changing over time. In fact, as our understanding of how we learn develops, and our knowledge of neurological structures and brain functions grows, our conceptualisation of Dyslexia changes. As it rightly should.

However, these changing definitions mean that parents and educators are often confused as to what conditions such as dyslexia are, and what they are not.

In summary:

It is a widely held belief that Dyslexia is a specific type of learning difficulty/disability, which manifests in people having difficulties in areas of literacy such as reading, spelling and writing. It’s a relatively common condition (affecting 5-20% of the population) that affects the way the brain processes written and spoken language.

Its causes are unknown, but believed to be neurological in nature. Specifically dyslexia is believed to be related to an individual’s genetic make-up and differences in his/her brain anatomy and activity. Underlying “cognitive” or as other theorists would say “processingdeficits related to Dyslexia are often found in phonological processing, auditory processing, and specific types of visual processing (often referred to as orthographic processing).

Dyslexia is also defined as an unexpected difficulty in reading in those who otherwise have the intelligence to learn to read.

It makes sense then, that a diagnosis of dyslexia should contain some measures of literacy, cognitive (or perceptual processing) strengths and weaknesses, AND a broader based overall measure of general intelligence in order to estimate a student’s overall intellectual potential.

Issues of using IQ assessment in Dyslexia Identification

One has to be careful when discussing the advantages or disadvantages of intelligence assessments in Dyslexia identification, because of the different conceptualisations of intelligence, held by the various theorists previously mentioned. That is, before the use of IQ assessment in dyslexia identification can be rejected, the concept and construct of intelligence must first be clearly defined.

There must be an understanding of what theory of intelligence is being used, which type of IQ or cognitive areas is being referred to generally, and what precise skills and sub skills are being referred to specifically. For example, if a Dyslexia specialist rejects the need for the use of IQ assessment in the identification of such a condition, exactly which types of intellectual areas or specific subtests are being rejected? Additionally, which (if any) perceptual processing tests are being used instead?

Issues may arise when different definitions of the skills being assessed are used interchangeably. For example, some literacy professionals choose to only examine and measure specific skills often associated with different types of Dyslexia such as auditory processing, phonological processing, and visual (orthographic) processing. Some cognitive theorists argue that such skills are best described as perceptual processing skills and are conceptually different to IQ. Others argue that such skills are in fact just different areas of intelligence.

Cumberland Education asserts that if a comprehensive test of intelligence is administered, then many different types of learning strengths and weaknesses can be captured – including skills such as auditory processing, phonological processing, and visual (orthographic) processing. If the IQ test of choice does not measure such skills, and/or if the assessor considers these skills to be separate processing skills (as opposed to cognitive skills) then these skills still need to be evaluated, but done under the auspices of an evaluation of perceptual processing.

Whilst IQ tests can be used to examine and measure both broad patterns of cognitive strengths and weaknesses, otherwise known as a learning profile, they can also be used to provide an estimate of a student’s overall level of intellectual ability and academic potential.

The concept of measuring intellectual potential is a controversial one (mostly concerning the relationship between IQ and reading achievement), and beyond the scope of this discussion. However, it can be said that whilst a student’s IQ scores can be underestimated for a variety of reasons (such as a lack of motivation, attention difficulties, Learning Difficulties, environmental depravation, mental health issues such as anxiety etc) an IQ score does provide an estimate of the minimum level a student is able to achieve. Hence, a minimum estimate of academic potential.

NOTE: From this point forward, the term “cognitive (perceptual)” will be used to acknowledge that skills such as phonological processing, auditory processing, and visual (orthographic) processing are viewed by some professionals as cognitive skills, and by others as perceptual skills.

What are the main costs to this method of diagnosis?

The recent trend of some educators is to ignore the role and value of comprehensive cognitive (perceptual) measurement in the identification of dyslexia, and instead focus on the functional aspects of literacy difficulties such as measuring reading, spelling and writing skills, in addition to only limited measures of cognitive (perceptual) skills related to literacy achievement such as phonological processing, rapid automatic naming, and orthographic processing.

It is my belief that there are costs involved with this new way of diagnosing and treating students with Dyslexia. These include:

  • Missing important information about a student’s broader cognitive or perceptual processing strengths and weaknesses.
  • Not differentiating between students who have significantly different levels of overall intellectual ability.

Missing important information about a student’s cognitive (perceptual) strengths and weaknesses

This new approach means an identification of Dyslexia has become more precise and refined. This in itself is not a bad thing. However, the issue with this change of focus is that it can come at the expense of a full evaluation of a student’s broader cognitive (perceptual) skills. Whilst these other unmeasured cognitive (perceptual) skills may not be directly related to Dyslexia, they may be related to other areas of learning or Learning Difficulties (LD), that impact more broadly upon a student’s performance.

Individuals who have LD are idiosyncratic. That is, they have unique patterns of cognitive (perceptual) strengths and weaknesses that underpin their various skills and difficulties, not only in specific learning tasks such as literacy, but in other areas of learning more generally. By only measuring skills such as phonological processing, rapid automatic naming, and orthographic processing, it is likely that other cognitive (perceptual) strengths and weaknesses will be overlooked or unaccounted for.

Literacy is only one aspect of learning, albeit a critical one. However, performing comprehensive cognitive (perceptual) assessments can explain student performance beyond literacy, to include information about ALL aspects of their learning.

In summary, by eliminating full cognitive (perceptual) assessment in the identification of one narrow type of LD- Dyslexia, you run the risk of “throwing the baby out with the bathwater”.

Not differentiating between students who have significantly different levels of overall intellectual ability

Some literacy specialists who do not perform comprehensive tests of intelligence as part of dyslexia identification, view that a student’s overall level of intellectual ability or potential is irrelevant or unimportant.

However, as stated above, individuals who have LD, including those with Dyslexia, are idiosyncratic. This applies as much to their individual and unique patterns of cognitive (perceptual) strengths and weaknesses, as it does to their overall level of intellectual ability (or IQ).

Cumberland Education asserts that having an estimate of overall IQ is both relevant and important, for not only educators, but for the students themselves.

For example, some students who experience difficulties in learning can have relatively low scores of intelligence, and others can have relatively high scores. For example, it is assumed that a child, who has an overall general level of ability e.g. IQ 140, is very different not only cognitively, but is also likely to be different emotionally and socially to a child of IQ 85. Such children are also often very different students to teach, because the causes of their poor reading are different.

Having this information on overall general ability is powerful for teachers and educators, but often more powerful for students themselves. Students have the right to know their level of intellectual potential, in order to contextualise why they may be having literacy difficulties. That is, especially true for students who have dyslexia, so they can attribute their difficulties to their specific LD, rather than being ‘stupid’ or ‘dumb’ as they so often feel.

The author has seen far too often, very bright students who perform at an average or slightly below average level, go unidentified as having any LD (including dyslexia). Instead they have gone through school, typically being told they were lazy or not trying hard enough. Often their self esteem is significantly affected, because they have not been able to attribute their difficulties in learning to the appropriate source. That is, often blaming their difficulties on inaccurate beliefs (i.e. being ‘stupid’ or ‘dumb’) instead of their specific LD.

Currently, a disadvantaged group of students in Australian schools are those who have high IQ, perhaps even meeting criteria for giftedness, but yet who only perform to an average or even lower level in different school subjects such as reading. This group of students are often left unidentified as having any underlying difficulties, such as LD (including dyslexia), and their gifts/talents often unrecognised. In turn they are unable to access any/relevant available support within the school system.

Under identification, of such students, occurs because of a lack of focus on students’ cognitive potential, measured via cognitive assessments. Instead, of educators being concerned with ‘below cognitive expectation’ or below ‘cognitive potential’, they are typically now concerned with student performance if seen as below average. This ‘below average’ approach will typically under identify this particular cohort of students mentioned above.

The reason for the change of focus to ‘below average’ rather than ‘below cognitive potential’, given by some theorists, is a claim that there is no, or little, relationship between IQ (overall cognitive/perceptual scores) and reading performance. Therefore, there is no need to measure IQ at all.

Whilst this argument is somewhat valid, in that you can be a poor reader even if you have a high IQ, an IQ score alone should not be used as a tool for LD diagnosis. Rather, a profile of cognitive (perceptual) strengths and weaknesses should be used, in addition to the IQ score being used as a useful tool in estimating a student’s learning potential.

For example, with all other learning conditions being equal, a student who has an above average level of overall intellectual ability (IQ) should be able to read to an above average level. If that student cannot- this should be investigated. The cause of this ‘below expectation’ performance may be due to various reasons such as lack of educational opportunity, emotional difficulties, lack of motivation or interest, a medical condition, or LD etc.

Similarly, if you are confident that you have a valid and reliable measure of IQ, and have accounted for all of the possible situations mentioned above, and a student has an Extremely Low IQ, one would not expect this student to be able to read to an Average or Above Average level. In fact, a student who has a high IQ but low reading score, requires different teaching methods to those provided for a student who has a low IQ but is reading to their expected/estimated level of potential.

In summary, the overall IQ scores can give the examiner an estimate of a student’s potential to achieve.

If one does not measure the student’s cognitive (perceptual) strengths and weaknesses, and determine an estimate of IQ, one misses a large amount of extremely helpful information regarding the student’s strengths and weaknesses, skills and abilities, and expected level of performance.

This is why, at Cumberland Education, we believe that a comprehensive assessment of literacy skills, cognitive (perceptual) skills, in addition to forming an estimate of a student’s learning potential, is essential for fully understanding student’s difficulties in learning generally, and difficulties such as Dyslexia more specifically.

If such assessment is not conducted, your run the risk of “throwing the baby out with the bathwater”.