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Summary

This research sets out a proposed protocol for the identification of dyslexia. The protocol is based on diagnostic and response to intervention models. The proposal involves using structured interviews and standardized tests for the assessment of reading and writing performance and determinant factors.

Abstract

In recent years, there has been an increase in the prevalence of dyslexia at early ages in different countries and regions. This increase has serious consequences within school and family settings, due to the poor academic performance that characterizes people with dyslexia and the socio-emotional problems they sometimes display. One of the most frequent problems in the identification of the dyslexia is the lack of a common diagnostic protocol that encompasses specific criteria for the assessment of any child. The Learning Disabilities and Development Disorders research group at the University of Malaga has developed a protocol for the early detection of dyslexia. The protocol is based on the diagnostic and response to intervention models. Consequently, it takes into account diagnostic criteria agreed upon by some associations and committees of experts, as well as certain specific cognitive and language determinants that characterize people who present with dyslexia following adequate instruction, according to recent research. The action protocol is developed over several stages, and we propose the use of structured interviews with parents and teachers alongside standardized tests for the evaluation of intelligence, reading and writing, as well as the risk factors that determine the appearance of the problem. This action protocol provides a model for the detection of dyslexia, which seeks to distinguish it from other comorbid problems and identify its characteristics and determinants, in order to offer effective intervention and/or prevention from an early age.

Introduction

The DSM-5 establishes specific learning difficulties as a diagnostic category within neuro-developmental disorders. Dyslexia has been considered one of the most common specific learning difficulties. It is characterized by difficulties with accurate and fluent word recognition, along with spelling and orthographical accuracy. It also entails difficulties in reading comprehension¹. These manifestations appear after the start of compulsory schooling, from the age of six onwards.

In recent years, there has been an increase in the prevalence of dyslexia at early ages. Some authors state that between 5% and 17.5% of school age children are affected by dyslexia^2,3. These percentages indicate the importance of considering early detection, since it has serious consequences within school and family settings, due to the poor academic performance that characterizes people with dyslexia and the socio-emotional problems they sometimes display.

In spite of this, there is often a lack of consensus about how to identify dyslexia. This is due to the on-going debate about the adequacy of identification criteria offered by the different explanatory models, derived from ambiguity in the definitions given in dyslexia. On the one hand, the traditional perspective advocates a model of diagnosis for the identification of these problems. More recently, however, the response to intervention model has emerged as an alternative for such purposes.

The diagnostic model considers several criteria when identifying dyslexia: the discrepancy criterion, the exclusion criterion and the specificity criterion (Figure 1, Figure 2, Figure 3, Figure 4).

Figure 1. Criterion of Diagnostic Model Please click here to view a larger version of this figure.

Figure 2. Discrepancy Criterion Please click here to view a larger version of this figure.

Figure 3. Criterion of Diagnostic Model (Exclusion Criterion) Please click here to view a larger version of this figure.

Figure 4. Criterion of Diagnostic Model (Specificity Criterion) Please click here to view a larger version of this figure.

The discrepancy criterion is based on the fact that people with dyslexia present a discrepancy between their intellectual potential and their performance. This criterion is not accepted by some authors who do not find it necessary to use IQ to determine the appearance of dyslexia^4,5. In contrast, other authors find that divergent children are more resistant to interventions than non-divergent children or that there are differences between them^6,7. Although the discrepancy criterion has been widely criticized, there does not appear to be consensus about its use. In our opinion, it is somewhat premature to dispense with IQ when it comes to identifying dyslexia. Discarding the use of IQ might make it hard to distinguish this problem from others such as intellectual disability. In this regard, discrepancy should be the first step in identifying dyslexia⁸.

The exclusion criterion refers to the difference between dyslexia and other specific disorders with which it occurs concomitantly. These disorders are usually sensory deficits, mental disability, emotional disturbances and socio-cultural or educational disadvantages^1,9. There is some controversy about the overlap between some of these disorders and dyslexia. Hence, for example, socio-emotional alterations and low social competence are sometimes included as characteristics of people with dyslexia, when it would actually appear that these difficulties are being generated by dyslexia¹⁰. Advocates for the use of the exclusion criterion argue that there is a risk that dyslexia will fall into a catchall category that encompasses other comorbid pathologies¹¹ if they are not considered for its diagnosis.

The specificity criterion implies certain restrictions with regard to the domains that are affected in dyslexia, such as language, reasoning and instrumental learning problems^1,9. Some authors argue that language problems should be included within the category of dyslexia^12,13. However, others believe that they should be differentiated and categorized as comorbid conditions, because language is acquired without formal education whereas other domains do require such instruction¹⁰. In this regard, dyslexia is characterized by problems with reading and writing, justified by difficulties in phonological processing^14,15 or a general sensory deficit^16,17. Those who argue that dyslexia is a deficit in phonological processing indicate that dyslexics present difficulties in tasks involving the effective use of the phonological code, presenting a deficit in the creation of phonological representations of words. As a result, they present difficulties acquiring the alphabetical principle and remembering grapheme-phoneme correspondences¹⁰. Proponents of dyslexia as a general sensory deficit argue that people with dyslexia present difficulties in tasks that require the processing of auditory stimuli presented quickly, displaying difficulties of auditory perception, owing to a deficit in their rapid temporal processing¹⁰. These basic difficulties give rise to phonological problems, which explain the difficulties they face recognising words.

The response to intervention model (RTI) integrates evaluation and intervention within the school system by means of a multi-level prevention system that maximizes the performance of students and reduces behavioural problems¹⁸. This model can be used to identify pupils who are at risk of manifesting reading and writing difficulties, monitoring their progress and offering interventions based on the pupil’s response. This model identifies people with dyslexia as subjects who do not respond to the intervention received by all students in the classroom and assume that it may be due to a cognitive or educational deficit¹⁹. The identification of dyslexia is a decision-making process, in which assessment will be interspersed with instruction. In each assessment stage, the progress made by students after each instruction stage is considered. So, if the performance assessment of the class as a whole is found to be adequate, the possible inadequacy of the instruction delivered is ruled out. Once it has been confirmed that instruction is adequate, the second stage involves identifying, by means of curricular measures, any students whose performance and progress is below that of their classmates, considering them to be students at risk of having dyslexia. In the third stage, individual curricular adaptations will be applied for these children. If these curricular adaptations are not sufficient, because the child is still not progressing, specialized educational measures are required, and the child is considered to be dyslexic^19,20,21 (Figure 5). This model focuses on academic performance, eliminates the IQ-performance discrepancy and assessments of intelligence, and reduces the number of false positives⁸. However, there are few criteria to determine whether a child does or does not respond well to intervention over time. In addition, these problems coexist with other issues, and non-response to intervention could be due to the existence of comorbidity between them^10,22,23. These studies are sceptical about the use of the RTI model as a diagnostic instrument.

Figure 5. Multilevel System of Model “Response to Intervention” Please click here to view a larger version of this figure.

Therefore, there does not appear to be any consensus regarding the criteria that should be used to identify specific learning disabilities, and, in particular, dyslexia. Whereas diagnostic models use discrepancy, exclusion and specificity criteria, the response to intervention model considers poor performance in basic instrumental tasks following adequate instruction as a criterion. Both models have been criticized and present certain weaknesses. For this reason, the Learning Disabilities and Development Disorders research group at the University of Malaga has developed a protocol for the early detection of dyslexia, which considers the strengths of the diagnostic model and the response to intervention model.

In short, the aim of this paper is to present a proposed protocol to detect dyslexia at an early age. It sets out to provide an objective diagnostic procedure for the assessment of this neurodevelopmental disorder, in order to differentiate it from other comorbid disorders, from an early age. For the diagnosis of this specific learning disability, the protocol takes into account the evaluation of certain specific cognitive and linguistic determinants after adequate instruction in reading and writing (response to intervention model), as well as the discrepancy, exclusion and specificity criteria (diagnosis model). The action protocol is developed over several stages, following different types of instruction, and we propose the use of structured interviews with parents and teachers alongside standardized tests for the evaluation of intelligence, reading and writing, as well as the risk factors that determine the appearance of the problem. This action protocol provides a dynamic model for the detection of dyslexia, which seeks to distinguish it from other comorbid problems and identify its characteristics and determinants, in order to offer effective prevention at an early age.

Protocol

This present study has been developed in accordance with the Helsinki Declaration, which establishes ethical principles for the development of research with humans. In addition, it follows the guidelines and was approved by the University of Malaga’s Experimentation Ethics Committee (CEUMA). NOTE: The protocol presented below should be carried out by psychologists within the school setting, beginning in the first year of Primary Education (6 years of age), and with the collaboration of teachers (Figure 6). Figure 6. Stage of Protocol of Evaluation of Dyslexia Please click here to view a larger version of this figure. 1. Stage 1: Assessment of instruction Inform parents that their children will be assessed, in order to analyze whether they are at risk of having dyslexia. Obtain informed consent from parents so that students can be assessed periodically. Assess the reading and writing performance, based on the curriculum (CBM), of all the students in class, following adequate reading and writing instruction in in their regular classroom20, for two hours every day over the course of approximately six months. For the assessment of reading and writing performance based on the curriculum, use the indicators recommended by the National Reading Panel (NRP): phonological awareness, knowledge of the alphabet, vocabulary, reading fluency and comprehension24. For the evaluation of these indicators, administer the test to detect dyslexia25,26 either collectively or individually, informing participants of the instructions for performing each test. Analyze the scores obtained. If the majority of the students have achieved similar appropriate scores in the assessment, rule out the possibility of inadequate teaching. 2. Stage 2: Multilevel assessment of student performance Level 1: Screening After analysing the scores obtained in stage 1, identify students who are at risk of dyslexia, according to the standards established for the tests administered. Include students identified as being at risk in the next level. Level 2: Assessment following group instruction After any students identified as being at risk have received frequent reading and writing instruction in small groups, (30 minutes, three to five times a week, for approximately 10 sessions), evaluate their response to that instruction, either collectively or individually24. To perform this assessment, administer screening tests for dyslexia25,26, which take the aforementioned indicators into account, informing the participants of the instructions to perform each test. Identify students who present a risk of dyslexia determined on the basis of low test scores, following the instruction received. Include the selected students in the next level. Level 3: Assessment following intensive instruction After students identified as being at risk have received even more frequent reading and writing instruction in smaller groups, evaluate their response to that instruction24. To perform this assessment, administer screening tests for dyslexia, collectively or individually25,26, which take the aforementioned indicators into account, informing the participants of the instructions to perform each test. Identify students who present a risk of dyslexia determined on the basis of low test scores, following the instruction received. Include the students selected in the next level. 3. Stage 3: Specific student assessment To corroborate the diagnosis of dyslexia among students identified as being at risk, carry out the following assessment protocol for each student. NOTE: Students who do not present any intellectual disabilities or sensory-motor handicaps, but who do perform poorly in reading comprehension and fluency and written accuracy, and present problems in most of the cognitive-linguistic variables evaluated, as well as possible socio-emotional, family and/or school repercussions, shall be classed as having dyslexia. Interview with parents To begin the specific student assessment protocol, inform parents that their child needs to be evaluated extensively because they have suspected dyslexia. Obtain informed consent from parents so that students can be assessed specifically. Conduct a structured interview with the student’s parents, in order to gather information about their child in terms of their personal development (biological, motor, sensory, social, communicative-linguistic) and the family setting (family history, family organisation, expectations about their child's difficulties, family impact of the child’s difficulties). Have the psychologist ask the parents about their child's development, the existence of family history and the family setting. Interview with the teacher Conduct a structured interview with the teacher, in order to find out their opinion about the problem their student might present, their personal development (motor, sensory, social, communicative-linguistic, style of learning and motivation), the classroom environment (class organisation, position of the student within the classroom, materials used by the student, the student's integration in the classroom) and their school record (schools attended, academic performance, diversity management measures received and approach to schooling). In this section, have the psychologist give the teacher the following instructions: "In order to obtain information and your opinion about the student, complete this structured interview referring to the student’s possible problem, their personal development, learning and motivation, their academic record and environment in the classroom". Measure of Intelligence Administer a cognitive scale27 to assess intelligence in children, in accordance with the instructions set out in the test handbook, in order to rule out possible intellectual limitations. Analyze the student profile obtained, in order to ascertain information about the cognitive and linguistic aspects (fluent reasoning, visual-spatial, working memory, processing speed and verbal comprehension) required to make the diagnosis and to establish the affected and unaffected cognitive-linguistic areas that would justify dyslexia and rule out other problems. Measure of Reading and Writing To measure reading fluency and comprehension, individually carry out a reading assessment25 for children aged six. In the reading fluency test, instruct the student to read a list of words and another list of pseudowords as fast as they can. Record the number they got right and the time they took to complete each test. Correct the answers in accordance with the correction criteria indicated in the test handbook. For the reading comprehension test, instruct the student to read a text in silence and then answer questions about what they have read. Record the answers given by the student and correct them in accordance with the correction criteria indicated in the test handbook. Analyze the student's reading profile in terms of accuracy, speed and comprehension, in accordance with the test instructions. To assess written accuracy, carry out the copying and dictation test with the student26, in accordance with the instructions indicated in the test handbook. To carry out the copying test, instruct the student to copy out several texts by hand in a maximum of one minute. Correct the student’s answers in accordance with the correction criteria indicated in the test handbook. To carry out the dictation test, instruct the student to write down by hand the words they will hear in a maximum of two minutes. Correct the student’s answers in accordance with the correction criteria indicated in the test handbook. Analyze the numbers of right and wrong answers from both tests, in accordance with the correction criteria indicated in the handbook. 4. Cognitive-linguistic measures After assessing reading and writing performance, evaluate the cognitive-linguistic variables that might explain the appearance of dyslexia24,28,29,30,31: phonological awareness, knowledge of the alphabet, naming speed, short-term memory, vocabulary, and phonological and semantic fluency. To assess phonological awareness, use a phonemic segmentation test26. In this test, instruct the student to repeat words after removing a certain syllable or phoneme. Write down the answers given by the student and correct them in accordance with the correction criteria indicated in the test handbook. To assess knowledge of the alphabet, use a letter reading test25. In this test, instruct the student to say the names of the letters shown to them on printed cards. Record the answers given by the student and correct them in accordance with the correction criteria indicated in the test handbook. To assess naming speed, use a test for the student to name pictures26. In this test, instruct the student to say the name of the pictures shown on cards as quickly as possible. Make a note of any errors and the time they take. Correct the test in accordance with the correction criteria indicated in the test handbook. To assess short-term memory, use an inverse digit test26. In this test, instruct the student to repeat in reverse order the sequence of digits they will hear. Write down the answers given by the student and correct them in accordance with the criteria established in the test handbook. To assess vocabulary, carry out a vocabulary test26. Instruct the student to simply mark the drawing that represents the word given by the examiner. Correct the student’s answers in accordance with the criteria established in the test handbook. To assess phonological fluency, use a verbal fluency test26. In this test, instruct the student to say in one minute all the words that begin with the sound /p/. Write down the answers given by the student and correct them in accordance with the criteria established in the test handbook. To assess semantic fluency, carry out a semantic fluency test26 and instruct the student to say in one minute all the animal names they know. Write down the answers given by the student and correct them in accordance with the criteria established in the test handbook.

Representative Results

This next section sets out a series of representative results obtained by one student diagnosed with dyslexia, following the proposed action protocol. Table 1 shows the scores obtained by Year 1 Primary students in phonological awareness, knowledge of the alphabet, vocabulary, and reading fluency and comprehension, after ordinary reading and writing instruction. The results indicate that most of the students achieve similar direct scores in the assessment, close to the average…

Discussion

In this study, we presented a proposed dyslexia detection protocol to be applied from Year 1 in Primary Education within the school setting. This action protocol considers the strengths of the diagnostic model^8,13,32 and the response to intervention model^{21,22,33,34,35</sup…}

Materials

PROLEC-R. Batería de Evaluación de los Procesos Lectores	TEA ediciones		This Instrument assess of reading performance
The dyslexia Screening Test-Junior	Pearson Assessment		Screening tests for dyslexia (writing, comprehension reading, phonological awareness, knowledge of the alphabet, vocabulary)
The Wescher Intelligence Scale for Children- 5 edition	Pearson Assessment		This instrument assess the intelligence