**2. Competing diagnostic models for identifying learning disabilities**

An important issue in the study of learning disabilities has been to reach a consensus on the definition of LDs and the criteria for identifying them. Since 1963, when Kirk first coined the term learning disabilities, a number of definitions have appeared to characterize these problems. Most of these definitions have focused more on what LDs are not, instead of what they actually are.

In recent decades, the definition established in 1994 by the National Joint Committee on Learning Disabilities (NJCLD) and backed by the main international diagnosis systems (e.g., the International Statistical Classification of Diseases and Related Health Problems (ICD-10) in 2015, and Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013) has become more widely accepted. Exclusion criteria are predominant in this definition, although the best procedures for quantifying these are not specified. Learning disabilities are considered to be a heterogeneous group of disorders that are manifest as significant difficulties in acquiring and using the skills of reading, writing, and solving mathematical problems. These disorders are intrinsic to the person: there may be accompanying handicaps (e.g., intellectual disabilities, severe emotional disorders, and sensory deficits), or extrinsic influences (such as cultural differences, and insufficient or inappropriate instruction), but learning disabilities are not the result of these conditions or deficits (NJCLD and DSM-5).

Learning disabilities are neurologically based–processing problems. These processing problems can interfere with learning basic skills such as reading, writing, and/or math. They can also interfere with higher-level skills such as organization, time planning, abstract reasoning, long- or short-term memory, and attention. Learning disabilities can affect an individual's life beyond academics and can impact relationships with family, friends, and in the workplace.

Recent research yields a diversity of models for identifying specific learning disabilities. Difficulties in learning reading and writing have received the most attention [1]. The identification of reading-writing LDs has varied in recent decades, differing between countries and over the years [1].

The traditional model for identifying these problems in many countries has been and continues to be a diagnostic criteria-based model [1]. These models have been the most popular for assessing specific learning disabilities, most notably models based on the concept of discrepancy [1]. The IQ/achievement discrepancy model is used internationally and has continued in use for longer [1]. This model claims that persons with reading-writing LDs are characterized by a discrepancy between their IQ and their achievement, that is, they have normal IQ but their reading and writing achievement is below the 20th percentile [2, 3].

Another reason has been the diversity of theories and hypotheses to explain the appearance of learning disabilities, the variety of factors that produce them, and the few studies that have analyzed predictive factors of reading and writing. An analysis of the main predictive factors of reading and writing will be offered here, based on recent research results in studies with

Finally, this chapter provides an analysis of the effects of some programs that have been developed to prevent reading and writing learning disabilities in different countries. We analyze the characteristics of the primary prevention programs, such as Success For All (SFA), Starting Out Right (SOR), Comprehensive Early Literacy Learning (CELL), and the Prevention

**2. Competing diagnostic models for identifying learning disabilities**

An important issue in the study of learning disabilities has been to reach a consensus on the definition of LDs and the criteria for identifying them. Since 1963, when Kirk first coined the term learning disabilities, a number of definitions have appeared to characterize these problems. Most of these definitions have focused more on what LDs are not, instead of what they actually are.

In recent decades, the definition established in 1994 by the National Joint Committee on Learning Disabilities (NJCLD) and backed by the main international diagnosis systems (e.g., the International Statistical Classification of Diseases and Related Health Problems (ICD-10) in 2015, and Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013) has become more widely accepted. Exclusion criteria are predominant in this definition, although the best procedures for quantifying these are not specified. Learning disabilities are considered to be a heterogeneous group of disorders that are manifest as significant difficulties in acquiring and using the skills of reading, writing, and solving mathematical problems. These disorders are intrinsic to the person: there may be accompanying handicaps (e.g., intellectual disabilities, severe emotional disorders, and sensory deficits), or extrinsic influences (such as cultural differences, and insufficient or inappropriate instruction), but learning disabilities are

Learning disabilities are neurologically based–processing problems. These processing problems can interfere with learning basic skills such as reading, writing, and/or math. They can also interfere with higher-level skills such as organization, time planning, abstract reasoning, long- or short-term memory, and attention. Learning disabilities can affect an individual's life beyond academics and can impact relationships with family, friends, and in the workplace.

Recent research yields a diversity of models for identifying specific learning disabilities. Difficulties in learning reading and writing have received the most attention [1]. The identification of reading-writing LDs has varied in recent decades, differing between countries and

The traditional model for identifying these problems in many countries has been and continues to be a diagnostic criteria-based model [1]. These models have been the most popular for

Program of Reading and Writing Learning Disabilities (PREDALE).

not the result of these conditions or deficits (NJCLD and DSM-5).

different languages.

64 Learning Disabilities - An International Perspective

over the years [1].

Some authors defend the discrepancy model, but specify discrepancies between oral comprehension and achievement as an alternative to the IQ/achievement discrepancy, asserting that IQ is not relevant in diagnosing reading and writing LDs [2, 3]. Elsewhere, other researchers have questioned the discrepancy model as a means of defining and identifying students with specific learning disabilities [4–8]. These researchers have recently proposed other diagnostic criteria not relating to discrepancy. Low achievement scores have been suggested as being sufficient to identify reading-writing LDs, given that the purpose is to identify a need for intervention, not IQ or an IQ/achievement discrepancy. Still, other authors look more to low scores in phonological awareness [9] or in cognitive processes, as diagnostic criteria for reading and writing LDs [10].

A more recent model in use today is based on the response to intervention model (RTI) [4–6, 10]. In 2004, the Individuals with Disabilities Education Improvement Act (IDEIA), in accordance with the Commission on Excellence in Special Education and the Office of Special Education and Rehabilitation Services of the US Department of Education, and with the National Associations of School Psychologists (NASP), proposed that the IQ/achievement discrepancy model be abandoned in favor of the RTI model. This means a considerable change in the conceptualization and identification of these problems. Since 2004, studies on the RTI model have become increasingly prevalent, having a substantial presence in the most prestigious journals, such as the *Journal of Learning Disabilities*, *Learning Disabilities Quarterly*, *Reading & Writing*, and *Reading & Writing Quarterly*.

This move toward RTI, however, has not occurred in every country or at the same time. For example, the change occurred earlier in Australia than in other countries (2001), and in the United Kingdom, Japan, and Germany, the IQ/achievement discrepancy model was never adopted, or it was abandoned more quickly, focusing more on the criterion of these children's need for reeducation [1, 11]. Based on this model, a child with difficulty learning to read and write is identified as having specific LDs based on his/her immediate response to instruction in written language, as long as there is severely low achievement and unexpected early difficulty in learning, manifest as a failure to respond to standardized instruction [4–6, 12, 18].

Even though most current studies defend the RTI model, some authors indicate that this model is effective for improving achievement in reading and writing only if certain conditions are met. Some studies show that the RTI model is effective for identifying these problems only at early ages (4–6-year-olds); it cannot adequately predict later reading achievement, and it may present many false positives [13, 14]. In other words, the RTI model is insufficient for identifying children with specific LDs, and it does not offer greater benefits than other models mentioned above [15].

Consequently, other studies [16, 17] put forward a new diagnostic model, the component model of reading (CMR), including three significant domains for identifying these problems: cognitive components (e.g., phonological awareness, decodification, vocabulary and comprehension), psychological components (e.g., motivation, locus of control, teacher expectations, gender differences, and learned helplessness), and ecological components (e.g., behavior at home, culture and parental involvement, classroom environment, peer influences, and dialects) [16, 17]. This model assesses reading and writing performance from a multidimensional perspective, and facilitates more adequate, individualized instruction, with better chances for success [17].

Finally, based on these research studies, some authors have proposed a fusion of the diagnostic and RTI models. This solution serves to evaluate students' skills and determine their academic needs, so that they may receive special education that is adequate for their needs [18]. There is a great need for further objective research.
