I would like to thank you for the wonderful information compiled on your DyslexiaHelp website. I have found it extremely helpful in educating myself about reading disability.

I read through all of the test descriptions trying to figure out why my son’s testing doesn’t reflect his struggles in reading. His CTOPP scores were average to above average despite displaying many signs of dyslexia and with a four-generation history of reading problems. His school has told me the CTOPP scores have ruled out dyslexia. My question is can one really rule out dyslexia based on the CTOPP? I understand that poor phonological awareness is the hallmark of dyslexia; but if the child has been receiving intervention, is it possible to score well on this test while still actually being dyslexic? I requested the TOWRE-2 testing after reading the many test descriptions on your website. I appreciate any information you can pass along.

Dr. Pierson's Response: 

You are very astute. The short answer to your question is yes - someone can absolutely score well on the Comprehensive Test of Phonological Processing - 2 (CTOPP-2) and be dyslexic. I can run into this when I evaluate children for dyslexia, particularly if the child has had structured literacy intervention. We know that structured literacy intervention works and positively impacts phonological awareness skills. In addition, improvement in phonological awareness skills can have positive outcomes on rapid automatic naming skills. This is why I always recommend getting a good diagnostic assessment as soon as possible, ideally, early and before intervention has begun. If a student has had an intervention, it can be more challenging to make the diagnosis of dyslexia, but it can be done.

The challenge with the CTOPP-2 is that the phonological awareness tasks are not timed. We really need a timed measure of phonological awareness skills. To my knowledge, there is not one. In his book Essentials of Assessing, Preventing, and Overcoming Reading Difficulties, David Kilpatrick is quite clear in noting that the reading brain, after learning how to read, continues to require additional time to process linguistic information. In other words, although they become readers, those with dyslexia continue to struggle with efficiency and are slow readers. As a diagnostician, it is my job to make the case that, despite average scores on the CTOPP-2, the student was slow and inefficient. The examinee can make multiple attempts to solve the phonological awareness tasks and still get credit. I find that the test score is not the most informative piece of the puzzle -- it is the behavior during the testing that is important to analyze and understand.

Many times, when testing a student, I have to make the case between "average" CTOPP-2 scores and the student’s understanding of spoken language. Recently, I saw a client who had spoken language comprehension (LC) skills at the 95th percentile (superior range), but CTOPP-2 scores on the phonological awareness composite at the 27th percentile (average range). The case I had to make was that her phonological awareness abilities were significantly discrepant from her LC skills (i.e., potential). This is part of the definition of dyslexia -- a child who is not achieving to his or her potential (see bolded text below).

“Dyslexia is a specific learning disability that is neurobiological in origin. It is characterized by the difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities…”” (Lyon, Shaywitz, & Shaywitz, 2003, Annals of Dyslexia, p. 2).

I have worked with students in many school districts where the staff did not understand this definition, or if they did, they were tied by the interpretive parameters of the special education code. In Michigan, where I am, many school districts continue to operate under the premise that a student must score below the 10th percentile in order to qualify for services under the category of specific learning disability. Thus, our students who score above the 10th percentile, but not in line with their receptive language skills, do not qualify for services.

You were correct in requesting the TOWRE-2. It is a timed measure and looks at the reading of both real and nonsense words. Many times, students who have had intervention will be able to accurately read the real words, but they are slow. And then, in regard to reading the nonsense words, they may struggle to decode the words because their phonological awareness skills and orthographic knowledge are not solidified. A good diagnostician will go beyond the test scores and conduct an error analysis to determine whether the errors made are indicative of dyslexia. At 3LI, it is our practice to give the TOWRE-2 during a diagnostic assessment and conduct an error analysis.

Last, family history is a significant red flag for dyslexia. According to the literature, if a child has a parent who has dyslexia, there is a 50% chance that he or she will also have dyslexia. That’s pretty high odds.

So, a good diagnostician will triangulate all of these data when making a diagnosis -- test scores; test item analysis; behavioral responses to performing test items; spoken language comprehension skills compared to written language skills; one’s learning history particularly in regard to reading, spelling, and writing; and, importantly, family history.

I’m impressed that you asked this question. It is a good one.