This post originally appeared on the Inside School Research blog.
The academic gaps related to dyslexia can show up in verbal deficiencies years before children traditionally are expected to read, and can continue well into the teenage years.
Dyslexia, a persistent difficulty in reading, is the most common learning disability, affecting about 1 in 5 school-age students. By 1st grade, children with dyslexia already show gaps in both verbal ability and intelligence compared to typically developing children, and those gaps persist into 12th grade, according to a new study published in the Journal of Pediatrics.
Sally and Bennett Shaywitz, co-directors of the Yale Center for Dyslexia and Creativity, tracked a subsample of 414 participants in the Connecticut Longitudinal Study, a 33-year, ongoing study of the emergence and effects of reading disabilities. From preschool into adulthood, the students participated in annual assessments, including, during the school years, Woodcock-Johnson reading tests and the Wechsler IQ scale for children.
Across fundamental reading skills, the Shaywitzes found students with dyslexia in 1st grade performed 1.5 standard deviations below typically developing readers, and those skills gaps remained at a full standard deviation in 12th grade. To put that in perspective: Students with dyslexia were still below a typical 1st grade reader’s skills in word identification and comprehension when they were in 2nd grade, and were not decoding as well as a typical 1st grade reader when they were in 3rd grade.
“We were surprised to find this very large gap present right away, early on in 1st grade,” Sally Shaywitz said. “Children are ready for and can be helped by evidence-based interventions, but no one is looking for [dyslexia] that early.”
The researchers identified several signs of dyslexia even before school, including young children mispronouncing words, having difficulty learning the names of letters in the alphabet, or being unable to find an object that starts with a particular sound—for example, pointing to a ball when told “buh.”
“You can look for signs when the child has trouble learning common nursery rhymes,” Sally Shaywitz said. “In order to appreciate common rhymes, you have to be able to pull apart spoken words to their component sounds, and the child can’t do that.”
As schools begin to teach formal reading and pre-literacy in preschool grades, she said, educators should consider screening students for potential reading difficulties even before they begin formal reading.