Learning: Dyslexia and Et Al.

Learning: Dyslexia and Et Al.

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Literature Review: An International Perspective on Dyslexia * Table of Contents Table of Contents2 Executive Summary2 Background2 Methodology4 Findings4 1. Introduction10 2. International Definitions12 3. Causes and Characteristics of Dyslexia19 4. Identification of Dyslexia24 4. 1Dyslexia Early Screening Test (DEST)25 4. 2Cognitive Profiling System (CoPS)32 4. 3Wechsler Intelligence Test for Children (WISC)34 4. 4Response to Intervention (RTI)35 5.

Intervention and Support39 6. Long-Term Prospects of Dyslexics56 7. Language and Dyslexia60 7. 1The Impact of Orthographic Consistency on Dyslexia61 7. 2The Impact of Alphabetic and Logographic Language Systems on Dyslexia63 8. Conclusions67 9. References69 APPENDIX 1-other tests available to identify dyslexic individuals84 APPENDIX 2-other commercial intervention programs86 APPENDIX 3-summary of issues raised during peer review process86 * Executive Summary Background Literacy is one of the competencies necessary for effective participation in modern life and is a prerequisite for the achievement of many other essential competencies, both generic and specific. It underpins access to all learning areas across the curriculum. New Zealand has a good reputation for the literacy achievement of its students, but it also has a system where a number of learners are not achieving well by international standards2.

There is a group of students who experience persistent and on-going difficulties in literacy, and recently there have been particular questions as to whether the current education system is meeting the needs of a group of students with specific learning disabilities (SLD), in particular those commonly referred to as dyslexia. Dyslexia is an often misunderstood, confusing term for reading difficulties, but despite the many confusions and misunderstandings the term dyslexia is commonly used by a number of medical personnel, researchers and the general public.

Identifying an individual as ‘dyslexic’ can help them to understand their experiences but this label does not give any information or direction on how to support and teach this individual to read and write. For this reason the term dyslexia is often avoided in educational contexts with preference given to the terms ‘learning disability’, ‘specific learning disability’ or ‘specific learning difficulty’. However, the continued use of the term dyslexia in research and by many members of the general public means that these phrases are often used interchangeably, as will be the case in this review.

The purpose of this literature review is to examine available international research and information over the last decade on dyslexia, with particular attention to the students that have been identified as “dyslexic”, the tools commonly used to identify these students, the support services that are available to these students and who provides these services. The overarching goal is to gather evidence on the effectiveness of interventions used to improve literacy levels of dyslexic students or students at risk of dyslexia in order to inform evidence based policy development within the New Zealand Ministry of Education.

As part of the peer review process for this literature review, James Chapman and Bill Tunmer from the College of Education at Massey University, Palmerston North were asked to provide feedback on the literature review in respect of the methodology, structure and comprehensiveness of the review; strengths of the review and/or any obvious gaps in terms of literature related to dyslexia; and the usefulness of the review. A summary of the issues raised during

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the peer review process can be found in appendix 3. Methodology Over the last decade there has been a considerable amount of research and writing within the area of dyslexia. The scope of this review was limited to the objectives stated in the section above. In particular, this project required a methodology that would enable location of high quality studies that demonstrated a clear relationship between literacy outcomes of dyslexic students or students at risk of dyslexia and specific components of teaching or support.

Searches were conducted using a number of databases and research web pages and a combination of key words. The abstracts or citations were screened and articles selected based on relevance to the review. The articles were sorted into categories, read by the author and rated for their validity in terms of the project brief. Articles describing experimental research studies were also rated according to criteria that support rigorous evidence3. However a number of studies fell short of these inclusion criteria.

The scope of the review was expanded to include studies that fell short on one or two of these criteria, to ensure a reasonable pool of studies to consider and identify the best available evidence. (Refer to Appendix 3, numbers 1 to 3 for peer review comments) * Findings Analysis across the research studies and reviews has identified a number of key findings from the authors that add to the knowledge base about dyslexia. Some congruency of findings between research studies has also been identified that are likely to contribute to the improved literacy levels of dyslexic individuals. 2 PIRLS 2001, PISA 2000 Randomised controlled trials, clear description of the intervention, who administered it, who received it, the costs, the sample size, the outcome measures are valid, the size of any effects are reported. Definitions of dyslexia The research on dyslexia revealed that there is no agreement on the definition of dyslexia across English speaking countries, nor is there agreement on its causes, subtypes and characteristics. However, there was a significant amount of evidence in the research reviewed to substantiate the following: * Dyslexia involves an unexpected difficulty in learning to read.

Although the exact causes of dyslexia are still unknown, an underlying theme evident across all the definitions is the notion that dyslexia involves an unexpected difficulty in learning to read. (Aaron, 1997; Stanovich, 1998, 1999; Lyon et al., 2003; Klassen, 2002, 2005; British Psychological Society, 1999; Velluntino et al., 2004) * Dyslexia is a specific learning disability. It has become widely accepted that dyslexia is a specific learning disability and has biological traits that differentiate it from other learning disabilities. (Lyon et al. 2003; Klassen, 2002, 2005; Ramus et al., 2003; Stein 2001; Velluntino et al., 2004) * Definitions involve a phonological deficit. Over the last decade, definitions of dyslexia have moved away from using IQ discrepancy models in the definition and moved towards accepting that a phonological deficit should be included in the definition. (Aaron, 1997; Stanovich, 1998, 1999; Lyon et al., 2003; Klassen, 2002, 2005; British Psychological Society, 1999) Causes and effects of dyslexia The research on dyslexia revealed that there is no agreement on the causes and effects of dyslexia.

However, the research reviewed revealed a significant body of evidence to support the following claims: *

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There are three main deficit theories on what causes the characteristics of dyslexia: * The phonological deficit theory explains difficulties dyslexic individuals show linking sounds with symbols in reading and spelling. * The cerebellar deficit theory suggests there is a problem in central processing linked to learning and automaticity. * The magnocellular deficit theory suggests that problems arise as a result of visual or auditory deficits. (Ramus et al. 2003; Lyon et al., 2003; Shaywitz et al., 1999; Blomert et al., 2004; Padget, 1998; Frith, 1997; Nicolson et al., 2001; Heiervang et al., 2002; Pammer & Vidyasagar, 2005; Stein, 2001) * Problems with phonology are associated with dyslexia. The phonological deficit theory as the underlying cause of dyslexia has gained wide acceptance and is by far the most researched and developed theory. Even though there is unanimous agreement that phonology is associated with dyslexia it is becoming clear that phonology is not the only problem. (Ramus et al., 2003; Lyon et al. 2003; Shaywitz et al., 1999; Blomert et al., 2004; Padget, 1998; Frith, 1997; Snowling, 2000) * The emotional response of a dyslexic individual becomes more significant with age. Children and adults with reading difficulties have an enhanced likelihood of associated emotional and social difficulties. Young at risk or dyslexic children have similar levels of self-esteem as normal children, however without effective instruction and support their self-esteem decreases, and after the age of 10 it is extremely difficult to help these children develop a positive self image.

Thus, without recognition of associated emotional or social problems it is possible that the gains made to treat the dyslexia will diminish if adequate support to assist the dyslexic individual is not offered. (Hales, 2001; Ryan, 1994; Muijs, 1997; Esser & Schmidt, 1994; Lindsay & Dockrell, 2000) The literature reviewed revealed limited or contradictory evidence in relation to the following claims: * Dyslexia is a neurological disorder with a possible genetic origin.

Brain imagery studies have shown differences in the anatomy, organisation and function of a dyslexics brain, but it is unknown whether these are a cause or effect of the reading difficulty. A gene may have been identified that is responsible for dyslexia and as this gene is dominant it would make dyslexia an inheritable condition. (Ramus et al., 2003; Lyon et al., 2003; Cardon et al.; 1994; Grigenko et al., 1997; Field & Kaplan, 1998; Habib, 2000) * Dyslexia is more common in males than females. A number of reports suggest that dyslexia is more frequent in males than females ranging from 1.:1 to 4. 5:1 but it is unclear whether this observation is a result of selection factors and/or bias. Until further controlled research is carried out the consensus is that dyslexia occurs in both sexes with equal frequency. (Wadsworth et al., 1992; Shaywitz et al., 1990; Ansara et al., 1981; Miles et al., 1998) . | Language of instruction. From the small amount of available literature, the strongest consensus is that the manifestations of dyslexia differ by language. The underlying causes of dyslexia are thought to be universal but it is likely that the core deficit differs with rthographic consistency. (Harris & Hatano, 1999; Ziegler & Goswami, 2003, 2005; Ziegler et al., 2003; Landerl & Wimmer, 2000; Helmuth, 2001, Wimmer

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et al., 1998) | . | Cost effectiveness. Any intervention is more cost effective with younger | students that are at risk of reading difficulties, compared to older students that have been identified with a reading disability. Also, interventions of 25 hours or more tended to be very poor in terms of cost effectiveness, especially for older children with known disabilities. (Fawcett, 2002; KPMG Foundation, 2006)

Enhancing literacy levels of dyslexics The research reviewed revealed a significant body of evidence to support the following claims: . | Early detection. Early success in reading skills usually leads to later success in reading, while failing to read before the third or fourth year of schooling may be indicative of life-long reading problems. Thus, early detection is best made in early childhood or during the first year of school where the gap that separates the students at risk of reading failure and the students that are likely to be successful readers is small.

Early detection alone however will not improve literacy levels unless the student receives appropriate early intervention before reading problems become entrenched. (Juel, 1988; Stanovich, 1986; Velluntino et al., 2004; Tunmer et al., 2003; Narayana & Xiong, 2003; Fuchs & Fuchs, 2001; Fawcett et al., 1998; Speece et al., 2003; Whiteley et al., 2002; Torgesen, 1998) | . | Maximising the chances for early identification of all at risk students. Tests | that should be administered for early detection aim to identify students at risk of dyslexia but make no attempt to diagnose dyslexic students.

Tests administered at a young age are more inaccurate than tests administered at an older age. Early identification procedures need to be carried out with as many children as possible to maximise the chances for identification of all at risk students. (Torgesen, 1998; Singleton et al., 1996; Woodcock et al., 2001; Fuchs & Fuchs, 2001; Nicolson & Fawcett, 1996) * Determine a student’s strengths and weaknesses. Assessment tools that determine a student’s strengths and weaknesses in a range of areas can be used to design individual intervention strategies that target the identified weakness areas.

These have greater benefit in an educational setting than a full psychometric test as they are relatively simple and quick screening methods that can be carried out by non-specialist staff. (Torgesen, 1998; Singleton et al., 1996; Woodcock et al., 2001; Fuchs & Fuchs, 2001; Nicolson & Fawcett, 1996; Wechsler, 2004; Velluntino et al., 2004; Whiteley et al., 2002) * Early intervention. Research has not been able to identify one type of intervention as better than another for teaching at risk or dyslexic readers, although all methods seem to work for some learners.

However, it has been found that early intervention, designed to improve the specific needs of the individual, reduces the prevalence of dyslexia compared to individuals who did not receive intervention or support. Students who had early intervention compared to remediation at an older age show bigger gains in reading accuracy and fluency. It is also easier for them to catch up with their peers, and the long-term cost of their education is lower. (Schneider et al., 1999; Borstrom & Elbro, 1997; National Reading Panel, 2000; Torgerson et al. 2006; O’Connor, 2000) * Instruction in phonological awareness and phonics at an early age. Timing issues with regard to preventative instruction have not been completely resolved by research but

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at risk students who had intervention in phonological awareness and phonics at an early age compared to remediation at an older age show bigger gains in reading accuracy and fluency. Also teaching phonological awareness significantly improves the reading of at risk or dyslexic students compared to an instruction that lacks attention to phonological awareness. Schneider et al., 1999; Borstrom & Elbro, 1997; National Reading Panel, 2000; Fawcett, 2002; Torgerson et al., 2006; Leafstedt et al., 2004) * Teaching focused on individual learners needs. Identification of effective intervention methods for at risk or dyslexic readers is a challenging process because every person with dyslexia is different. To be effective these interventions need to be focused on each individual learner’s strengths and weaknesses, and have the flexibility to change with the needs of the individual. (Whiteley et al. 2002; Given & Reid, 1999; Torgesen, 2000; Velluntino et al., 2004; Alexander & Slinger-Constant, 2004) * Increased intensity. It is agreed that once reading difficulties have been identified teaching efforts must immediately be intensified. However, research has not revealed what level of intensity, frequency or instructor to student ratio is most effective, and these are likely to vary across interventions. (Pressley, 2001; Hiebert & Taylor, 2000; O’Connor, 2000; Torgesen, 1998, 2001, 2002; National Reading Panel, 2000; Velluntino et al. 2004; Alexander & Slinger-Constant, 2004) * On-going assessment and support. Dyslexia is a lifelong disability and research has shown that there are no quick fixes for dyslexic students. Owing to the dynamic course of language development and the changes in language demands over time, even after a child has demonstrated a substantial response to treatment, their subsequent progress should be carefully tracked to ensure optimal progress toward the development of functional reading and written language skills. (Pressley, 2001; Hiebert & Taylor, 2000, Shaywitz et al. 1999; Velluntino et al., 2004; Torgesen, 1998) The literature reviewed revealed limited or contradictory evidence in relation to the following claims: * Fluency instruction. Although intuitive, there is insufficient evidence to suggest that encouraging children to silent read more has an effect on fluency, accuracy or comprehension; however guided repeated oral reading shows positive signs of improving word recognition, fluency and comprehension. (National Reading Panel, 2000; Fawcett, 2002) * Comprehension instruction.

Preliminary findings with learning disabled readers suggest that comprehension develops from vocabulary strength, fluent word reading and a combination of strategies for helping students connect with and think about the text. (National Reading Panel, 2000; Fawcett, 2002; Swanson & Hoskyn, 2000) * Computer assisted instruction. Computer technology is showing great potential for improving reading achievement, with promising approaches for promoting word recognition and vocabulary and comprehension development. (Swanson & Hoskyn, 2000; Pressley, 2001; National Reading Panel, 2000) * Teaching strategies.

Results suggest that learners benefit from teachers who are able to offer a range of teaching strategies and have access to a wide range of instructional materials and resources. (Swanson & Hoskyn, 2000; Department of Education and Skills, 2004a; Lyon et al., 2003) * Adults can be taught using the same elements identified to teach children. It is never too late for individuals with dyslexia to learn to read and use other language skills better. However, rigorous research studies to determine the most effective interventions for adolescents and adults are just underway.

Initial results show that the same elements identified to teach children can be used for older individuals, and intensive, evidence based remedial interventions can improve reading accuracy

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in older reading disabled or dyslexic individuals, but these are less effective at closing the fluency gap. (Alexander & Slinger-Constant, 2004; Velluntino et al., 2004; Ramus et al., 2003) In conclusion, it can be seen that over the last decade a large amount of research on dyslexia has been undertaken, but how these findings fit together to form an overall picture still remains elusive.

This literature review has identified a number of key factors that the research has found to contribute to improving the literacy levels of at risk or dyslexic readers. However, due to the limited number of rigorous research studies carried out in New Zealand the impact of these findings on improving literacy levels of at risk or dyslexic New Zealand students needs to be researched further. The current challenge is to design and undertake rigorous research studies that assess the effectiveness of these international findings in a New Zealand setting. Introduction

The term “dyslexia” was coined in 1887 to refer to a case of a young boy who had a severe impairment in learning to read and write in spite of showing typical intellectual and physical abilities. Research on dyslexia throughout the early 20th century focused on the idea that dyslexia stemmed from a visual deficit that involved reading words backwards or upside-down. However, in the 1970s it was suggested that dyslexia stemmed from a deficit in processing the phonological form of speech, which resulted in individuals having difficulty associating word sounds with visual letters that make up the written word.

More recent studies using modern imaging techniques have shown differences in the way the brain of a “dyslexic” person develops and functions. Now, even after a century of research, dyslexia is still one of the most controversial topics in the field of developmental neurology, psychology and education. The controversy arises from the incomplete and varying definitions of dyslexia and from the contradictory theories surrounding its causes, subtypes and characteristics. Dyslexia is widely accepted to be a specific learning disability and has biological traits that differentiate it from other learning disabilities.

Dyslexia is the most common specific learning disability and is estimated to affect from 3 to 20 % of the population around the world. The Specific Learning Disabilities Federation of New Zealand (SPELD NZ) which provides specialist tutoring services within New Zealand estimate that 7. 1 % of all students have specific learning disabilities, which equates to approximately 55,000 school age children. However there is no empirical evidence to confirm this statement. Findings from the 1996 International Adult Literacy survey (Chapman et al., 2003) have 7. % of New Zealand adults identifying themselves as having a reading disability; based on today’s population this equates to around 265,000 adults. However, as the survey only focused on reading problems and not all possible learning difficulties it is reasonable to assume that at least 10 % of the population experiences some type of specific learning disability. Whilst the term dyslexia is used in some countries as a type of specific learning disability, there is no international agreement on its definition and diagnosis. The New Zealand government does not officially recognise the use of the term dyslexia to define literacy difficulties.

Currently, the Ministry of Health does not

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recognise dyslexia as a medical condition but recognises that it needs diagnosis and treatment, and as it is considered a developmental disorder the preferred term is specific learning disability. The Ministry of Education does not wish to develop an education system which defines and categorises students in terms of their learning disabilities, but prefers a system that makes assessments on their needs for additional support. In this regard, the Ministry of Education does not specifically recognise the se of the term dyslexia in the school context because of the issues associated with labelling students, and instead, individual needs are identified and appropriate interventions across a range of learning difficulties are implemented. Provisions have been made in the Special Education 2000 policy for schools to assist children with moderate learning difficulties and a Special Education Grant (SEG) is also paid directly to schools so that they might provide instructional adaptations to improve the educational achievement of those students with learning difficulties.

Remedial reading programmes offered to New Zealand students with reading difficulties include Reading Recovery (RR), and specialist support is provided through the Resource Teachers: Literacy (RT:Lits) and Resource Teachers: Learning and Behaviour (RT:LBs). However, there is a group of students who are not making progress in literacy in spite of good teaching and, where accessed, any intervention. It is possible that this may result because of learning disabilities that teachers know little about.

Recently, there have been particular questions as to whether these interventions are meeting the needs of a group of students with the specific learning disability recognised as dyslexia in other countries. The purpose of this literature review is to examine teaching initiatives and international research over the past decade on dyslexia, and to see whether there is evidence that these international initiatives have improved the literacy levels of “dyslexic” students. International Definitions

Each of the following definitions of dyslexia, from English speaking nations, emphasise a slightly different feature or view about the nature or cause of the difficulty. It should be noted that the term ‘dyslexia’ is mostly a medical term and often avoided in educational contexts, with preference in North America given to the term ‘learning disability’ or ‘specific learning disability’. In the UK and Australia the term ‘specific learning difficulty’ is preferred. However, the continued use of the term ‘dyslexia’ in research and by the public means that these phrases are often used interchangeably, as will be the case in this review.

In the USA the Office of Special Education and Rehabilitative Services within the US Department of Education provides funding and is committed to improving results and outcomes for people with disabilities of all ages. In keeping with the governments No Child Left Behind agenda (US Department of Education, 2001) and the Individuals with Disabilities Education Act (US Department of Education, 2004) the Office of Special Education and Rehabilitation services provides a wide array of supports and services to parents, individuals, school districts and states to serve individuals with learning disabilities.

In the USA operational definitions of learning disabilities are undergoing a move away from the traditional IQ achievement discrepancy definition to identification based on

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other markers (Aaron, 1997; Stanovich, 1998, 1999). The move away from traditional IQ achievement is demonstrated by looking at the change in the National Institute of Child Health and Human Development (NICHD) definition of dyslexia over the past few decades.

In the 1980s they had an exclusionary definition of dyslexia: ‘If a child’s difficulty with reading could not be explained by low intelligence, poor eye sight, poor hearing, inadequate educational opportunities, or any other problem, then the child must be dyslexic. ’ This definition was unsatisfactory to a number of parties including parents, teachers and researchers, and once research in dyslexia began at NICHD, the definition was revised. In 1994 a working definition of dyslexia was put forward (Lyon et al. 2003): ‘Dyslexia is one of several distinct learning disabilities. It is a specific language-based disorder of constitutional origin characterised by difficulties in single word decoding, usually reflecting insufficient phonological processing. These difficulties in single word decoding are often unexpected in relation to age and other cognitive and academic abilities; they are not the result of generalised developmental disability or sensory impairment.

Dyslexia is manifest by variable difficulty with different forms of language, often including, in addition to problems with reading, a conspicuous problem with acquiring proficiency in writing and spelling. ’ This working definition was revised in 2003 to the current definition: ‘Dyslexia is a specific learning disability that is neurobiological in origin. It is characterised by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities.

These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction. Secondary, consequences may include problems in reading comprehension and reduced reading experience that can impede growth of vocabulary and background knowledge. ’ The exclusionary definition adopted in the 1980s has now moved towards a more non-categorical definition.

Dyslexia is now identified as a specific learning disability and recognises the advances in understanding of the neural basis for dyslexia since the previous definitions. The new definition expands on the difficulties in single word decoding in the previous definition to specifically include difficulties with accurate word recognition and decoding. It also recognises poor spelling and the inability to read fluently as characteristics of dyslexia. New in the current definition is the concept that a child needs to have been provided with effective classroom instruction.

The addition of the final sentence describes the consequences of phonological difficulties and provides a causal model that can guide assessment efforts. The International Dyslexia Association has also adopted the 2003 NICHD definition of dyslexia. The history of dyslexia in Canada can be viewed as paralleling that in the USA (Klassen, 2002). The funding for dyslexic students sits within the special education division, the definitions of dyslexia have been similar and over the last few years have come under increased pressure to be revised.

In the USA and Canada operational definitions of learning disabilities are set by the individual states and provinces respectively, and thus there is considerable variation of the services and definitions used to determine access to service. These inconsistencies have added to

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the confusion surrounding the learning disabilities label (Shaw et al., 1995). In the Canadian education system dyslexia is classed under the category of learning disabilities and all but two of the provinces define a learning disability through the use of IQ scores in conjunction with discrepant achievement.

Even though there is variation between provinces on the definition of learning disability, the current official national definition of learning disabilities is taken to be the 2002 revision definition adopted by the Learning Disabilities Association of Canada (Learning Disabilities Association of Canada, 2002): ‘”Learning Disabilities” refer to a number of disorders which may affect the acquisition, organization, retention, understanding or use of verbal or nonverbal information. These disorders affect learning in ndividuals who otherwise demonstrate at least average abilities essential for thinking and/or reasoning. As such, learning disabilities are distinct from global intellectual deficiency. Learning disabilities result from impairments in one or more processes related to perceiving, thinking, remembering or learning. These include, but are not limited to: language processing; phonological processing; visual spatial processing; processing speed; memory and attention; and executive functions (e. g. planning and decision-making).

Learning disabilities range in severity and may interfere with the acquisition and use of one or more of the following: * oral language (e. g. listening, speaking, understanding); * reading (e. g. decoding, phonetic knowledge, word recognition, comprehension); * written language (e. g. spelling and written expression); and * mathematics (e. g. computation, problem solving). Learning disabilities may also involve difficulties with organizational skills, social perception, social interaction and perspective taking.

Learning disabilities are lifelong. The way in which they are expressed may vary over an individual’s lifetime, depending on the interaction between the demands of the environment and the individual’s strengths and needs. Learning disabilities are suggested by unexpected academic under-achievement or achievement which is maintained only by unusually high levels of effort and support. Learning disabilities are due to genetic and/or neurobiological factors or injury that alters brain functioning in a manner which affects one or more processes related to learning.

These disorders are not due primarily to hearing and/or vision problems, socio-economic factors, cultural or linguistic differences, lack of motivation or ineffective teaching, although these factors may further complicate the challenges faced by individuals with learning disabilities. Learning disabilities may co-exist with various conditions including attentional, behavioural and emotional disorders, sensory impairments or other medical conditions. For success, individuals with learning disabilities require early identification and timely specialized assessments and interventions involving home, school, community and workplace settings.

The interventions need to be appropriate for each individual’s learning disability subtype and, at a minimum, include the provision of: * specific skill instruction; * accommodations; * compensatory strategies; and * self-advocacy skills. ’ However, a specific definition of dyslexia is also used by the Canadian government which is taken from the British Columbia Health Guide (British Columbia Health Guide, date unknown): ‘Dyslexia is defined as having difficulty with the alphabet, reading, writing and spelling in spite of normal to above average intelligence, conventional teaching, and adequate socio-cultural opportunity.

Dyslexia is thought to be both genetic and hereditary. Dyslexia is not caused by poor vision. Dyslexia is identified following psychological

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and educational tests that determines language and other academic abilities, IQ and problem solving skills, and is only identified if the reading disability is not a result of another condition. ’ The Canadian Dyslexia Association has a variation on this and states that: ‘Dyslexia results from a different brain organisation.

This may cause problems with reading, writing, spelling and speaking, despite average or superior intelligence, traditional reading instructional and socio-cultural opportunity. The biological condition of dyslexia is hereditary. ’ In British Columbia changes in the way learning disabilities are defined have recently attracted attention as a review of special education services in British Columbia has been carried out (Siegel; Ladyman, 2000). In this review there is a significant change from the definitions of the last three decades and the proposed changes reflect some of the most current research.

The authors argue that ‘a significant number of studies examining learning disabilities have found no difference in the reading (including reading comprehension), spelling and phonological skills between learning disabled individuals with high and low IQ scores, and that there are no differences between dyslexics and poor readers on measures of the process directly relating to reading. ’ These changes mean that identification of learning disabilities will occur at the classroom level by teachers using standardised tests. It is thought that this process will detect most, if not all learning disabilities.

British Columbia appears to be leading the way in North America in the move to eliminate the need for IQ tests in the learning disabilities identification process with the aim to shift emphasis from eligibility to appropriate intervention (Pasternack, 2002). However, as almost all the other American states and Canadian provinces use IQ tests as part of the learning disability identification process, the resolve to move away from this practice has bought about confusion about the nature and structure of learning disability identification practices in the future (Klassen, 2002).

Education systems outside North America have definitions in which discrepancy techniques are not used in identifying learning disability. These countries have either never adopted the IQ achievement discrepancy or have already moved away from this method of identifying students with dyslexia or learning difficulties. In Britain the funding for children with dyslexia sits within the Special Education Needs and Disability Division of The Department of Education and Skills.

The governments strategy for special education needs, Removing Barriers to Achievement (Department of Education and Skills, 2004), sets out the governments vision for giving children with special needs and disabilities the opportunity to succeed. This strategy has built on the proposals for the reform of children’s services set out in the governments’ key policy Every Child Matters. In Britain the term ‘dyslexia’ was previously avoided in education with preference given to the term ‘specific learning difficulties. However, as the term dyslexia was embedded in everyday language it has gradually gained acceptance and has recently been included in key policy documents (Department of Education and Skills, 2001, 2004). The Department of Education and Skills worked closely with the British Psychological Society on a report to clarify the concept of dyslexia within an educational context (British Psychological Society, 1999). This report

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expressed the need to define dyslexia in a descriptive way without explanatory elements. A working definition was proposed that would be the starting point to different rationales and research initiatives.

This working definition is the current definition of the British Psychological Society: ‘Dyslexia is evident when accurate and fluent word reading and/or spelling develops very incompletely or with great difficulty. This focuses on literacy learning at the ‘word level’ and implies that the problem is severe and persistent despite appropriate learning opportunities. It provides the basis of a staged process of assessment through teaching. ’ It has been reiterated that this is only a descriptive working definition and not an operational definition.

The following two definitions by other British associations use explanatory elements in their definitions of dyslexia. The British Dyslexia Association definition is that: ‘Dyslexia is best described as a combination of abilities and difficulties that affect the learning process in one or more of reading, spelling, writing. Accompanying weaknesses may be identified in areas of speed of processing, short-term memory, sequencing and organisation, auditory and/or visual perception, spoken language and motor skills. It is particularly related to mastering and using written language, which may include alphabetic, numeric and musical notation. The British Dyslexia Institute states that: ‘Dyslexia causes difficulties in learning to read, write and spell. Shortterm memory, mathematics, concentration, personal organisation and sequencing may also be affected. Dyslexia usually arises from a weakness in the processing of language based information. Biological in its origin, it tends to run in families, but environmental factors also contribute. Dyslexia can occur at any level of intellectual ability. It is not the result of poor motivation, emotional disturbance, sensory impairment or lack of opportunities, but it may occur alongside any of these.

The effects of dyslexia can be largely overcome by skilled specialist teaching and the use of compensatory strategies. ’ In Australia, dyslexia advocacy groups have had little influence on dyslexia identification practices within the education system (Elkins, 2001). During the 1960s and 1970s dyslexia was a funded category with identified students receiving support through remedial classes. The students at this time were identified as having average intelligence but were two years behind their peers in reading (Klassen et al., 2005).

However, a formal government committee set up in the early 1970s argued against formalising a definition of learning disability, and against categorical funding for those experiencing specific learning difficulties. Australia currently has a system similar to New Zealand in which a non-categorical/low achievement approach to the funding of learning disabilities is taken. This means that students with specific learning disabilities are not individually funded, but funding and a variety of intervention programs are offered to help increase the literacy skills of low achieving students.

The main source of this funding is through the Literacy, Numeracy and Special Learning Needs Programme, which is an Australian Department of Education literacy and numeracy initiative. Across the English speaking nations the definitions of dyslexia vary considerably. However, over the last decade there has been a move away from using discrepancy models in the definition of dyslexia and a move towards accepting that a phonological

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deficit should be included in the definition. It has also become widely accepted that dyslexia is a specific learning disability and has biological traits that differentiate it from other learning disabilities.

However, the exact causes of dyslexia are still unknown and there is no agreement between communities and countries on its definition, subtypes and characteristics. Even though all the definitions vary the underlying theme that is evident through all the definitions is the notion that dyslexia involves an unexpected difficulty in learning to read. (Refer to appendix 3, number 4 for peer review comments) Causes and Characteristics of Dyslexia The international definitions of dyslexia vary considerably between countries and associations with no agreement on its causes and characteristics.

The only consensus between the definitions is the notion that dyslexia involves an unexpected difficulty in learning to read; where reading itself can be defined as the process of extracting and constructing meaning from written text for some purpose (Vellutino et al., 2004). Even though this is the one agreed characteristic that individuals with dyslexia will display, there are numerous other possible characteristics reported in the literature that may be an indication of dyslexia.

These include, but are not limited to, difficulty with (Davis; Braun, 1994; British Psychological Society, 1999; Bright Solutions for Dyslexia, date unknown): * formation of letters; * naming letters; * associating sound (phonetics) with the symbol (grapheme); * writing letters of the alphabet in the proper sequence; * spelling, writing; * finding a word in the dictionary; * following instructions; * expressing ideas in writing; * distinguishing left from right, east from west; * telling time, days of week, months of year; * short term or working memory; * inconsistent performance and grades; * lack of organisation; automatisation of tasks; and * balance; It should be noted that the characteristics of dyslexia can vary greatly from one individual to another, and not all individuals will have problems with all these difficulties. Also individuals who do have difficulties with these skills may not be dyslexic. (Refer to appendix 3, number 5 and 6 for peer review comments). The exact causes of dyslexia which result in the display of some of the characteristics shown above are still not completely clear. However, from the research literature there are three main deficit theories that may cause the identified characteristics of dyslexia.

These deficit theories are (i) the phonological theory (Ramus et al., 2003; Lyon et al., 2003; Shaywitz et al., 1999; Blomert et al., 2004; Padget, 1998; Frith, 1997), this is by far the most researched and developed theory over the past decade; () the cerebellar theory (Ramus et al., 2003; Nicolson et al., 2001); and (i) the magnocellular (auditory and visual) theory (Ramus et al., 2003; Blomert et al., 2004; Heiervang et al., 2002; Pammer; Vidyasagar, 2005; Stein, 2001). From a decade of literature there are different versions of each theory, which have developed over time.

Described here is, as far as the author is aware, the current, most prominent version of each theory. (Refer to appendix 3, number 7 for peer review comments). (i) The Phonological Theory This theory is based around speech sounds, and postulates that dyslexic individuals have difficulties in representing, storing and/or retrieving these sounds. In dyslexics the difficulty in reading in relation to this theory is a consequence of impairment in the

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ability to learn to read an alphabetic system which requires learning the grapheme-phoneme relationship.

In simple terms there is impairment in the ability of relating written letters to their speech sounds. This theory implies a straightforward link between a cognitive deficit and difficulty in reading. Support for this theory comes from evidence that dyslexic individuals perform particularly poorly on tasks requiring phonological awareness. There is also evidence that suggests dyslexics have poor verbal short-term memory and slow automatic naming which suggests a more basic phonological deficit (Snowling, 2000; Ramus et al. 2003). At a neurological level, anatomical work and brain imaging clearly show that a dysfunction with the left side of the brain is the basis for the phonological deficit (Lyon et al., 2003; Temple et al., 2001; Marshall, 2003; Frith, 1997). However, despite all the evidence supporting the phonological theory the quote taken from Frith (1997) sums up the current status of the theory; “the precise nature of the phonological deficit remains tantalisingly elusive. ” () The Cerebellar Theory

This theory postulates that the dyslexics’ cerebellum is mildly dysfunctional and that a number of cognitive difficulties will ensue, including balance; motor skill; phonological skill and rapid processing (Nicolson et al., 2001; Ramus et al., 2003; Fawcett, 2001). As a number of these skills are not language based, the phonological theory could not explain all the problems associated with dyslexia. Problems in motor skill and automatisation point to the cerebellum, but until recently this was largely dismissed in dyslexia because there were no known links between cerebellum and language.

However, there is now evidence that the cerebellum is involved in both language and cognitive skill, including involvement in reading (Fulbright et al., 1999). Support for this theory comes from evidence of poor performance of dyslexics in a variety of motor, time estimation and balance tasks (Fawcett et al., 1996; Fawcett; Nicolson, 1999). Brain imaging studies have also shown anatomical, metabolic and activation differences in the cerebellum of dyslexics (Brown et al., 2001; Ramus et al., 2003). (i) The Magnocellular (Auditory and Visual) Theory

Historically, visual and auditory disorders were considered separately but there is now agreement between their advocates that they come under the more general area of a magnocellular dysfunction (Stein; Walsh, 1997; Ramus et al., 2003; Tallal et al., 1998). This theory postulates that the deficit lies in the perception of short or rapidly varying sounds or difficulty processing the letters and words on a page of text. This theory does not exclude a phonological deficit, but emphasises the visual and auditory contribution to the reading problem.

Evidence to support this theory includes differences in the dyslexic brain anatomy in both visual and auditory magnocellular pathways (Stein, 2001), and the co-occurrence of visual and auditory problems in certain dyslexics (van Ingelghem et al., 2001). In summary the phonological theory explains many of the difficulties which dyslexic individuals show linking sounds with symbols in reading and spelling. The cerebellar theory suggests there is a problem in central processing linked to learning and automaticity.

The magnocellular theory suggests that the problems a dyslexic individual may display are a result of visual and auditory deficits. Each theory also has weaknesses or problems associated with it. The phonological theory does not explain the occurrence

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of sensory or motor disorders that occur in a significant proportion of dyslexics, while the magnocellular theory suffers mainly from its inability to explain the absence of sensory and motor disorders in a significant proportion of dyslexics. The cerebellar theory presents both types of problems.

Even though these theories are usually considered separately, it is evident that there is a synergy between these theories, and of course, it is possible that all three theories are true for different individuals. A number of studies carried out since the turn of the century have emerging findings that may make up another theory of dyslexia which is not based on a deficit theory, this is known as the transactional theory of dyslexia. The transactional view draws on work based on cognition (Anderson, 2003), socio-cultural (Gee, 2001) and learning theories with a more instructional focus (Clay, 2001).

In this regard it postulates that reading ability is not a property of the reader but varies depending on the complex social contexts and events in which it occurs. The transactional view on reading difficulties advocates that understanding the natural variability of readers is more important and productive than diagnostic categories (McEneaney et al., 2006). (Refer to appendix 3, number 8 for peer review comments). From advances in anatomical and brain imagery studies it has been recognised, but not universally, that dyslexia is a neurological disorder with a possible genetic origin, since it occurs most often in families (Ramus et al. 2003; Lyon et al., 2003). Some researchers think they have identified a gene responsible for dyslexia, and as this gene is dominant it makes dyslexia an inheritable condition (Cardon et al.,1994; Grigorenko et al., 1997). More current research has however found no evidence of an association or linkage between the identified gene and dyslexia (Field; Kaplan, 1998). So the genetic origin of dyslexia, if there is one, is still a hotly debated subject and continues to be the focus of modern day research.

Researchers have agreed that brain imagery studies have shown differences in the anatomy, organisation and function of a dyslexic person’s brain, but it is unknown whether these differences are a cause or effect of the reading difficulty (Lyon et al., 2003; Brown et al., 2001; Stein, 2001). There are also a number of reports that dyslexia is more frequent in males than females, ranging from 1. 5:1 to 4. 5:1 depending on the study (Wadsworth et al., 1992; Shaywitz et al., 1990; Ansara et al., 1981; Miles et al., 1998) but it is unclear whether this observation is due to selection factors and/or bias.

Until further controlled research is carried out the current consensus is that dyslexia occurs in both sexes with equal frequency. (Refer to appendix 3, number 9 and 10 for peer review comments). The last decade of research has made significant advances in the possible causes of dyslexia, with a possible neurological basis of the disability being recognised, but unfortunately there is still no answer or agreement on the exact causes of dyslexia. There is however unanimous agreement that problems with phonology are associated with dyslexia but it is becoming increasingly clear that phonology is not the only problem. Identification of Dyslexia

Early detection of dyslexia and other learning difficulties is desirable

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in order to obtain appropriate help for the student. Identification of dyslexic students is usually made during the first years of primary school when reading and writing problems are found that go beyond the normal starting difficulties. A formal psychological evaluation is the only method, across all Englishspeaking countries, that is recommended for diagnosis of dyslexia. (Refer to appendix 3, number 11 and 12 for peer review comments). In practice however, the lack of international agreement on the definition and causes of dyslexia means a differential diagnosis is ot possible and the formal evaluation just looks for a number of indicators that may suggest an individual is dyslexic. Also, in the USA and Canada because the definition of dyslexia differs between states and provinces the eligibility criteria differs, which may result in a child not being recognised as having a learning disability just by crossing a state/provincial border. This situation undermines the credibility and integrity of any identification process, in that it assumes that under any of the definitions currently in use that a learning disability is therefore not permanent or intrinsic (Klassen, 2002).

A full formal evaluation would be carried out by trained specialists and involve: * Social and family history; * Cognitive testing; * Educational testing; * Classroom observation and review of educational data; * Medical examination; and * A debrief of observations and recommendations In practice, due to time and money constraints, such comprehensive testing is very rarely completed and quicker, simpler screening tests are usually administered to detect signs or indicators of dyslexia. A number of tests have been designed for use in the cognitive testing part of the formal evaluation.

These tests can also be administered in isolation but in these cases they are used as a screening tool to identify students ‘at risk’ of dyslexia, but make no attempt to diagnose dyslexic students. However, it should be noted that identification of at risk students alone will not improve their literacy levels; they also need to receive appropriate intervention. These cognitive tests determine a student’s strengths and weaknesses in a range of areas, indicating possible intervention strategies that target the identified weakness areas. The theories behind these tests have been described in detail in the previous chapter.

Evaluation of the research literature shows that some tests are better supported by scientific evidence than others and information about standardisation varies across the variety of tests. Table 1 describes a number of tests that are available but is not intended to be exhaustive. Appendix 1 includes a more exhaustive list of available tests but descriptions are not provided. It was hoped by researchers that the development of screening tests would allow identification of children at risk of dyslexia before they fail to learn to read, that is by age 6 or younger.

Early screening for dyslexia provides a number of clear advantages, but despite excellent research in the area, until recently viable measures have not been available in any English-speaking country. The following sections of this chapter describe two screening tests that have become educationally acceptable in the UK; the Dyslexia Early Screening Test (DEST) and the Cognitive Profiling System (CoPS); and the two screening tests recommended in

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US Policy and used extensively in North America; (Wechsler Intelligence Test for Children (WISC) and Response to Intervention (RTI).

In the UK the majority of teachers are not fully trained to recognise dyslexia and other learning difficulties, but the Code of Practice (1994) states that teachers are expected to identify all levels of dyslexia and other learning difficulties and put an individual education plan (IEP) into practice immediately. Development of DEST and CoPS, specifically designed to be delivered by personnel largely untrained in psychometric testing, provided a solution to this problem (Fawcett et al., 1998).

These screening tools have been translated into a number of different languages and their use in other English-speaking countries is also increasing, and with the introduction of RTI in the Individuals with Disabilities Education Act (IDEA, 2004) in the US, these or similar screening tools will be needed. Dyslexia Early Screening Test (DEST) The DEST is designed to be administered by a teacher in the first term of school and takes about 30 minutes per child. DEST is not intended to replace Table 1. A selection of tests available to identify dyslexic individuals Test | Year | Description | Theory | Research |

Aston Index (Newton; Thompson, 1982) | 1982 | Designed for use by classroom teachers. Tests involve 2 levels, L1 for screening children who have been at school 6 months, L 2 for children over 7 years. Test scores are considered to be ‘mental age’ and are compared to example scores for a child’s chronological age supplied in a manual. | Magnocellular | Sutherland and Smith (1991) conclude that the test is rather dated, has limited use for pupils over 11 years and is difficult to interpret. Pumfrey (1985) and McGhee (1996) are critical of information in the manual on the construction, standardisation and validation of the Index. Bangor Dyslexia Test (Miles, 1997) | 1983 1997 | Administered as part of a clinical review to pupils over the age of 7. It involves positive indicators of dyslexia through 10 individual tests. | Cerebellar Phonological | The items comprising the test were developed from clinical data using 291 subjects (Miles 1993). The test cannot be considered a psychometric instrument and interpretation depends more on clinical judgement than dyslexia positive test scores. | Children’s Test of Non-word Repetition (Gathercote; Baddeley, 1996) | 1996 | A test of short term memory using 40 non-words.

The test is standardised with children aged between 4 and 8 years | Cerebellar | This test is thought to compliment tests specifically designed to assess phonological processing. Standardised data is reported using 612 children between 4 and 8 years. Studies of reliability show good correlations and validity is demonstrated through 2 small studies (Gathercole et al., 1994; Turner 1995). | Dyslexia Screening Test (DST) and Dyslexia Early Screening Test (DEST) (Nicolson; Fawcett, 1996) | 1996 2003 | The tests are designed to be administered by a teacher or psychologist and take about 30 minutes..

The DST is normalised for children age 6. 5 to 16. 5 and the DEST for children age 4. 5 to 6. 5. Each tests comprises of 10/11 subtests covering a range of tasks. The test yields an overall ‘at risk’ score and a profile of abilities, but do not attempt to identify dyslexia. | Phonological Cerebellar Magnocellular | These tests take into account research evidence from all three theories of dyslexia. The discriminatory power of these tests are however based on the

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authors own research (Nicolson; Fawcett, 1990, 1995) and independent validation by other authors is currently not yet available. Test | Year | Description | Theory | Research | Lucid Cognitive Profiling System (CoPS) (Singleton et al., 1996) | 1996 | This is a computerised standardised assessment system for use by teachers or psychologists with children aged 4 or 5. There are 8 main tests which are presented as games. A graphical profile of results is automatically calculated at the end of the test, and a manual is provided to interpret the profile. | Phonological Cerebellar Magnocellular | The research behind CoPS involved a 5 yr longitudinal study of 400 children.

The final tests were selected from 27 on the basis of accuracy and reliability. The tests have all been shown, independently and in combination, to have significant correlations with later literacy development. | Phonological Abilities Test (Muter et al., 1997) | 1997 | The test contains 4 phonological awareness subtests, a speech rate subtest and a letter knowledge subtest. It is recommended for children aged 5 to 7 years. It is primarily a tool to identify children who are ‘at risk’ of reading failure due to slower phonological development, not to identify dyslexia. Phonological | Standardised data for the test is from 826 children aged between 4 and 8 years. Studies of reliability and validity are reported in the manual, and authors advise caution when interpreting results | Phonological Assessment Battery (PhAB) (Frederickson et al., 1997) | 1997 | The battery of tests is designed for use by psychologists, special education teachers and speech therapists to assess phonological processing. The supplied manual gives information on interpretation and programme planning. Phonological | Standardised and normalised data for the test was collected from 629 pupils aged 6 to 15 years. Validity of the test was assessed in a study involving 89 children with recognised SLD, with these children achieving lower on the tests than a representative sample of children of the same age group. A study by Fredrickson and Wilson (1996) using rhyme analogy training suggested that the PhAB tests are sensitive to the effects of intervention and could be used in programme evaluation. | Test | Year | Description | Theory | Research |

Self-Perception Profile for Learning Disabled Students (Renick; Harter, 1997) | 1997 | It is a self-report questionnaire designed to assess children’s judgements of their competence, worth and esteem in particular areas. The questionnaire consists of 46 items, divided into 10 sections. The results are compared to standardised data supplied in the manual. | NA | Standardised data was collected from 201 SLD pupils and 367 of their peers aged 9 to 13 years. Reliabilities, patterns, means and standard deviations by section and year group are reported, along with guidance on interpretation.

Using these profiles for SLD pupils is relatively new but Boetsch et al (1996) report results which show that dyslexic children, compared to controls, perceive themselves as having lower intellectual ability, lower academic competence and lower global self worth. These profiles may be useful in identifying the areas of competence which influence a child’s self worth. | Wechsler Intelligence Test for Children (WISC) (Wechsler, 1992, 2004) | 1992 2004 | This is the most frequently used diagnostic instrument for assessing intelligence for use with children age 6 to 16 years.

A students score in 4 academic tests (ACID) are compared to scores on the other tests which determine cognitive status and potential for learning. The procedure for identifying an ACID profile is outlined in

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the WISC-I and WISC-IV (Wechsler, 1992, 2004). Children with dyslexia are considered to be those that perform badly on the ACID tests, however, wide scatter and discrepancies are also an important diagnostic sign. | Phonological Cerebellar | Standardised data on each subtest score and IQ scores is based on the scores of 2200 children nationwide (US).

Compared to the other tests there is substantial data in the literature on the use of WISC and ACID profiles. Some authors have claimed that the ACID profile is of value in the identification and diagnosis of dyslexia (Vargo et al., 1995). However, the majority of studies criticise the ACID test due to the lack of clear specification of subjects, absence of normal control group, wide age ranges and small sample sizes (Frederickson, 1999; Miller; Walker, 1981; Greenblatt et al., 1991) | Test | Year | Description | Theory | Research |

Woodcock Johnson I (WJI) (Woodcock et al., 2001) | 2001 | There are two separate but co-normed batteries of tests (Tests of Cognitive Abilities and Tests of Achievement)

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