01 NRDC Dyslexia 1-88 update - Texthelp

148
Research Report
Appendix 3
Some research criteria used in studies of
dyslexia
Caveat: ‘ … the majority of research investigations seeking to elucidate the
characteristics of dyslexia … have yielded findings that are difficult to interpret,
replicate, and generalise’ (page 7). Lyon, G. R. (1995). ‘Toward a definition of dyslexia’.
Annals of Dyslexia, 45, 3–27.
Study Construct group(s) Selection criteria
Bourassa, D. and Treiman, R.
(2003). ‘Spelling in children with
dyslexia: analyses from the
Treiman-Bourassa early spelling
test’. Scientific Studies of
Reading, 7(4), 309-333.
Dyslexic (vs. younger,
spelling-level matched
non-dyslexic) children
For dyslexia: Prior classification by
their schools as developmentally
dyslexic and then full-scale standard
IQ score of at least 85, performance
below the 25th percentile for their age
group on both spelling and reading
subtests of the Wide Range
Achievement Test-3 (based on the
combined performance across the two
forms of each subtest) and
performance below the fourth-grade
level on the spelling subtests of the
Wide Range Achievement Test-3,
based on the combined performance
across the two forms.
Pogorzelski, S. and Wheldall, K.
(2002). ‘Do differences in
phonological processing
performance predict gains made
by older low-progress readers
following intensive literacy
intervention?’ Educational
Psychology, 22(4), 413–427.
Dyslexic (vs. garden
variety) low-progress
readers
For the study: attendance at a
programme for children who were at
least two years behind in reading
accuracy, socially disadvantaged and
at serious risk of disaffection from
school.
For dyslexia: severe reading disability
as defined by the Phonological
Assessment Battery, i.e. scores falling
one SD below the mean on at least
three out of the nine subtests.
Chiappe, P., Stringer, R., Siegel, L.
S. and Stanovich, K. E. (2002).
‘Why the timing deficit hypothesis
does not explain reading disability
in adults’. Reading and Writing,
15, 73–107.
Reading-disabled (vs.
age-matched and
reading-level matched
normally-reading)
children
For reading disability: reading at or
below the 25th percentile on the
reading subtest of the Wide Range
Achievement Test-3, which is an
untimed confrontational naming task.
Heiervang, E., Stevenson, J. and
Hugdahl, K. (2002). ‘Auditory
processing in children with
dyslexia.’ Journal of Child
Psychology and Psychiatry, 43(7),
931–938.
Dyslexic (vs. normal
control) children
For dyslexia: At the first stage, a score
below the 10th percentile on a spelling
test administered by teachers; at the
second stage, a mean score of at least
2 SD below the mean age level on five
reading tasks from a standardised
battery of computerised reading tests.