My husband and I are currently in the midst of having our nearly 7-year-old son evaluated for dyslexia. His IQ is at the 91st percentile on the WISP; his receptive vocabulary skills range from the 91st to the 95th percentile depending on the test and his mathematical and problem solving abilities range from high average to very superior range depending on the test. He was also diagnosed with a severe speech articulation delay at age 4 (4th percentile on the Goldman-Fristoe test). He is currently struggling to read. Despite a book- and reading-rich environment and intensive classroom instruction, he was still classified as an emergent reader at the conclusion of grade 1. On the Gray Oral Reading test, his fluency and accuracy is at the 37th percentile. On measures of phonological awareness that take fluency into account, such as the AIMS web phonemic segmentation and nonword fluency measures, he scores at the 4th percentile. On CTOPP measures, however, which did not take fluency into account, he scored within normal limits (but average or slightly below average). However, on those non-timed tasks, he is extremely slow in responding and the process of decoding the sounds clearly fatigues him greatly. He also scored at a borderline level on the Judgment of Line Orientation test and very, very low on the coding subscale of the Wechsler. However, he scored very high (91st percentile) on Berry's test of visual motor integration.

We had a neuropsych evaluation, but the psychologist classified our son as not having dyslexia or any reading problem because he was within normal limits on phonological awareness and reading skills. This classification is inconsistent with the reality of life with our son and inconsistent with his teacher's evaluations of his skills. I should note that my husband and I are both Ph.D.s. I am also a psychologist and understand the tests and the issues involved in testing.

My question is this: Should fluency be taken into diagnostic account on measures of phonological awareness? In my understanding of dyslexia, fluency is crucial, so I do not understand why our son’s considerable lack of fluency is not being considered diagnostically.

Any assistance or advice you could provide would be greatly appreciated.


Dr. Pierson's Response: 

Without either seeing the report on your son or, moreover, seeing him personally, it's difficult to definitively say whether he is dyslexic or not, but based on what you wrote about your son, there does seem to be data to suggest dyslexia. The definition of dyslexia states that the child's reading and/or skills are not commensurate with other areas of cognitive ability. When we diagnose dyslexia at my private clinical practice we look at the child’s spoken language understanding and use and then compare the written language performance to that. Indeed, some children may have "average" skills in decoding or fluency or spelling; but when the performance is compared to their superior spoken language (or IQ, which we do not test for), there is a large discrepancy, and therefore, they are diagnosed with dyslexia. And, not surprisingly, we see a lot of kids with this very profile.

Being a psychologist, as you know, 15 points (or 1 standard deviation—SD) is considered significant on most standardized assessments (IQ, language, reading, etc.). According to your numbers above, there appears to be as much as -2 SDs or more between your son's IQ and his performance on the literacy measures. That score on the AIMS is more than -3 SDs! These discrepancies are indicative of dyslexia. Moreover, scores below the 10th percentile are considered clinically disordered and should get someone's attention regardless.

And, yes, fluency should absolutely be considered. It is one of the hallmarks of dyslexia. The double-deficit hypothesis outlines 3 "types" of dyslexia: 1) difficulties in phonological awareness only; 2) difficulties with reading fluency only; and 3) difficulties in both phonological awareness and fluency. Naming speed has been associated with a variety of reading skills, and in particular, it has been found to be closely related to sight word recognition, reading rate, and orthographic skill (i.e., understanding and facility with letter patterns and spelling rules).

Last, your son's history with articulation problems also raises a flag. We know that children with articulation problems can be at increased risk for developing reading and spelling problems. I think it behooves you to get a new assessment from someone who understands the current definition of dyslexia and how to assess and diagnose dyslexia. You can click on your state here and see if there is a qualified provider in your area. Not everyone on these lists have the expertise to assess and diagnose. You will want to be sure the professional has both expertise and experience.