Study Challenges Conventional Thinking About Dyslexia : Reading: Findings conclude that the disability may appear and disappear from one year to the next.
In a finding that challenges certain assumptions underlying special-education policies, a team of researchers has concluded that dyslexia is not an “all-or-none phenomenon” and may come and go in a child from one grade to the next.
The researchers found that dyslexia, believed to affect 12% to 15% of all U.S. schoolchildren, may occur in degrees “like obesity or hypertension”--contrary to the conventional thinking that dyslexia is an absolute, such as eye color.
The controversial conclusions come amid mounting pressure to diagnose learning disabilities as early as possible in a child’s school career and then to channel children classified as dyslexic into programs aimed at teaching them to read.
“The possible benefits of early diagnosis must now be tempered by the knowledge that as many as two-thirds of the children given this diagnosis early . . . will not meet the criteria for reading disability two years later,” the researchers contended.
The report, by a team at Yale University School of Medicine and published today in The New England Journal of Medicine, was met with skepticism from some experts who challenged the study’s methods and said they feared the findings would be misconstrued.
“One possible explanation for (their findings) is that they haven’t identified dyslexic students in the first place,” said Jeannette Fleischner, a professor of education at Columbia Teachers’ College in New York.
“The biggest danger is that people would over-generalize from their conclusions and recommendations and cease efforts to identify kids with dyslexia early in their school careers,” said Fleischner, who specializes in learning disabilities.
Dyslexia is a disorder in which people of otherwise normal intelligence have great difficulty learning to read. In such cases, a child’s reading skills lag far behind his or her other scholastic abilities and overall IQ.
Some dyslexic children tend to transpose letters within words, though that tendency is not necessarily a part of the disorder. Others have difficulty spelling, may not be able to read words they can spell and may be unable to write from dictation.
Dyslexia is viewed as separate from other reading problems, such as those linked to brain damage, mental handicaps or problems of speech and vision. Some researchers believe its cause may be a neurological disorder, which in some cases may run in families.
In the federally funded study, the Yale researchers tracked the reading development of 414 randomly selected schoolchildren from first through sixth grade. They defined dyslexia as a gap between reading achievement and achievement predicted by IQ testing.
They found that all the children’s reading ability varied in any given year and from year to year. This suggests, they said, that reading ability, even among dyslexics, is not constant over time but varies predictably in all children from year to year.
Specifically, they found that 72% of children classified as dyslexic in first grade would not be classified as dyslexic in third grade, even without remedial programs. Similarly, some who would not be classified as dyslexic in first grade would be in third.
“Reading difficulties, including dyslexia, occur as part of a continuum that also includes normal reading ability,” said the authors, led by Dr. Sally E. Shaywitz. “Dyslexia is not an all-or-none phenomenon, but like hypertension, occurs in degrees.”
That finding challenges current public policy for kindergarten screening and early identification of dyslexic children, which is based on the premise that the disorder is a discrete entity and remains stable over time, the researchers said.
They also urged caution in assuming that any particular intervention program had cured a child’s reading disability, since without any intervention, many children classified as dyslexic will no longer be classified that way two years later.
Finally, they suggested that criteria that define dyslexia narrowly as a clear-cut condition may not be valid. They said “children who do not meet these arbitrarily imposed criteria may still require and profit from help.”
Specialists in the field were mixed in their reactions to the paper.
Fleischner of Columbia Teachers’ College said the criteria the researchers used to identify dyslexia did not include certain critical diagnostic tests, raising the possibility that they counted as dyslexic some children who were not and perhaps missed some who were.
“It certainly will stir a lot of discussion,” Fleischner said of the paper. “But I think among the community of researchers who work in the area it won’t change people’s minds that dyslexia is a real condition that can be diagnosed and that requires special intervention.”
To Dr. Peter B. Rosenberger, director of the learning disorders unit at Massachusetts General Hospital, one of the most important findings in the paper is that “methods of identifying dyslexia are still deficient.”
For example, he said schools define dyslexics as intelligent children reading below their grade level. But such a definition can miss bright children reading at their grade level despite their dyslexia, but who could be reading at a higher level with help.
“More research is needed on this,” said James F. Kavanagh, deputy director of the Center for Research for Mothers and Children at the National Institute for Child Health and Human Development. “We don’t know. It’s still a big, fat puzzle.”
