Early Identification of Dyslexia
Early Identification Procedures - Also see our page on Signs of Dyslexia
As stated earlier in this paper, the earlier intervention is provided, the easier deficiencies are to overcome. Joseph Torgesen, a Distinguished Research Professor of psychology and education at Florida State University has been part of the research effort sponsored by the National Institutes of Health to identify the nature, causes, and best approaches to instruction for children with moderate to severe reading problems. In his article, “Catch Them Before They Fall: Identification and Assessment to Prevent Reading Failure in Young Children,” he focuses on early identification of children at risk for problems in learning to read.
Torgesen cautions that in selecting procedures for early identification of children at risk for reading difficulties, it should be noted that prediction accuracy increases significantly the longer a child has been in school. He noted that prediction of reading disabilities from tests given at the beginning of first grade is significantly more accurate than from tests administered during the first semester of kindergarten. This is due to the widely varying range of children’s preschool learning opportunities. Children may score low on early identification instruments in the first semester of kindergarten simply because they have not had the opportunity to learn the skills. However, if pre-reading skills are actively taught in kindergarten, some of these differences may be reduced by the beginning of the second semester of school. Torgesen recommends the screening procedures that will be described not be used until the beginning of the second semester of kindergarten.
Torgesen admitted that batteries containing multiple tests generally provide better prediction than single instruments, but he doesn’t believe the increase in efficiency is large enough to warrant the extra time and resources required to administer them.
His identification procedure involves administration of two tests:
A test of knowledge of letter names or sounds.
A measure of phonemic awareness.
Measures of letter knowledge continue to be the best single predictor of reading difficulties, and measures of phonemic awareness contribute additional predictive accuracy. “In our experience, tests of letter-name knowledge are most predictive for kindergarten children, and tests of letter-sound knowledge are most predictive for first graders (Torgesen).
Research in phonological awareness began in the 1970s and since then, more than 20 different tasks have been used to measure awareness of phonemes in words. Torgesen groups these measures into three broad categories: sound comparison, phoneme segmentation and phoneme blending.
Sound comparison tasks – a number of different formats are used that require children to make comparisons between the sounds in different words. A child might be asked to indicate which word from a list begins or ends with the same sound as a target word. For example: Which word begins with the same first sound as cat: boy, cake or fan? Additionally, tasks that require children to generate words that have the same first or last sound as a target word would fall in this category. Sound comparison tasks are among the least difficult measures of phonemic awareness and are particularly appropriate for kindergarten-age children (Torgesen).
Phoneme segmentation – these tasks involve counting, pronouncing, deleting, adding, or reversing the individual phonemes in words. This type of task requires pronouncing the individual phonemes in words: Say the sounds in cat one at a time. Additionally, tasks requiring deleting sounds from words are required: Say card without saying the /d/ sound (Torgesen).
Phoneme blending – This skill has only been measured by one kind of task, the sound-blending task in which the tester pronounces a series of phonemes in isolation and asks the child to blend them together to form a word: What word do these sounds make, /f/ - /a/ - /t/? Easier variants of the sound-blending task can be produced by allowing the child to choose from two or three pictures the word that is represented by a series of phonemes (Torgesen)
Sound comparison measures are sensitive to emergent levels of phonological awareness, while segmentation and blending measures are sensitive to differences among children during later stages of development involving refinements in explicit levels of awareness (Torgesen).
One measure of phonemic awareness that Torgesen suggests is suited for early identification purposes, 5-9 years, and is widely used is the Phonological Awareness Test. Published in 1995, the test contains five different measures of phonemic awareness: segmentation of phonemes, phoneme isolation, phoneme deletion, phoneme substitution, and phoneme blending.
The phoneme isolation test, which requires children to pronounce the first, last, or middle sounds in words, has the most appropriate level of difficulty for kindergarten screening and any of the others could be used for first- or second-grade assessments (Torgesen).
The test also has a measure of sensitivity to rhyme, which Torgesen said is not included in his earlier list of measures of phonemic awareness because he believes they appear to be measuring something a little different, and less predictive of reading disabilities from those measures that ask children to attend to individual phonemes. For the same reason, measures of syllable awareness are not included in this group (Torgesen).