Intervention for Dyslexia - The British Dyslexia Association

visual information with neurological systems subserving verbal memory, auditory
processing and phonology. Furthermore, several studies have produced evidence that
sensory and motor impairments affect only a subset of dyslexics and cannot by
themselves explain the phonological deficit in reading disability (see Ramus, Rosen et
al., 2003). White, Milne et al. (2006) found that only about 20% of a sample of dyslexic
children had motor deficits, but all except one of these children also had deficits in
phonology and the one exception also had visual stress. In a meta-analysis of 17
published studies that compared balance function between dyslexia and control samples,
Rochelle and Talcott (2006) concluded that the effects in these studies were highly
influenced by the nature of the samples used, and that in studies where there appeared
to be evidence suggesting impaired balance function in dyslexia the most probable
explanation was that the samples had included participants with symptoms of attention
deficit hyperactivity disorder (ADHD) and/or below average IQ. Hence it would appear
that motor deficits are associated not with dyslexia per se, but with attentional problems
that are sometime co-morbid with dyslexia.
Many teachers who use either the DEST or DST (or both) confess to not using the
Postural Stability subtest. In part, this may be because they are aware of the scientific
controversy surrounding this test and its theoretical underpinnings, but the main reason
given is that they do not feel comfortable administering this test because it involves the
child standing upright with feet together and being given a measured push in the back
by the teacher, who is required to make a subjective judgement regarding the extent to
which balance is upset.
4.3.4 Computer-based screening tests for dyslexia
The advantages of computer-based assessment in education have been explored by
Singleton (1991; 1994a, 1994b, 1997b, 2001). Computers provide more precise
measurement, especially when complex cognitive skills are being assessed. Tests are
administered in an entirely standardised manner for all persons taking the test, which
enhances reliability of measurement. Timings and presentation speeds can be controlled
precisely. The subjective judgement of the test administrator does not affect the test
outcome as it can in conventional tests. Results are available immediately, and when
assessing older children and adults, assessment can be largely self-administered: both of
these factors help to reduce administrative load and avoid delays. Because the items
and instructions are delivered entirely by computer, supervision of the screening can be
provided by teaching assistants or personnel other than teachers.
Many computer-based tests are adaptive, conferring considerable efficiencies of time. In
an adaptive test the difficulty of the items selected from a test bank is varied in
response to the child’s progress on the test. Adaptive computer-based assessment takes
about 25% of the time taken by equivalent conventional tests (Olsen, 1990). As well as
being time-efficient, adaptive testing is psychologically-efficient because it selects test
items that are within the child’s Zone of Proximal Development (ZPD), thus avoiding
both the frustration and/or demotivation that can arise in a conventional or non-adaptive
test when the child is confronted with many items that are too hard for them, as well as
the boredom associated with being required to tackle large numbers of very easy items.
Children frequently express a preference for computerised assessment compared with
conventional assessment (Horne, 2002; Singleton, 2001). Some computer-based tests
can be run on a school network, and consequently can be administered simultaneously
to groups of children, thus affording further economies of time. However, when
screening younger pupils a greater degree of supervision is usually required.
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