One of the challenges is that children with reading disabilities are not a homogeneous group. That’s why it takes a combination of tests to recognize a reading disability. For instance, in a group of seven children with reading disabilities who have been followed since infancy, Smith says she has seen at least three different profiles.
“What I’m seeing in these profiles is a combination of language strengths and weaknesses,” she says. However, all have problems with phonology (the sound system of language) at some point.
For example, some toddlers do not have overt signs of language weaknesses until they hit preschool age. Then it is discovered that they have difficulty with the deletion test (the “cat” to “at” example), Smith says. While some children have difficulty with other language skills such as vocabulary or syntax as early as toddlerhood, others only show weakness in phonological skills. In spite of normal language comprehension skills, children with this weakness may be diagnosed with a specific reading deficit known as dyslexia.
Dyslexia is one of the most commonly recognized reading disabilities, but Smith says not all children and adults with reading disabilities are dyslexic. Many with reading disabilities have trouble with reading comprehension, not with decoding words.
Youngsters with dyslexia often slip through the cracks because they can memorize whole written words, says Smith. However, the strategy will only work up to a certain reading level before beginning to break down, often at fourth or fifth grade when the complexity of reading material in school greatly increases.