05 - 6A03 Developmental learning disorder

6A03 Developmental learning disorder

Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural or Neurodevelopmental Disorders Boundary with diseases of the nervous system and other medical conditions classified elsewhere Loss of previously acquired skills in language and social communication in the second year of life is reported in some children with autism spectrum disorder, but this rarely occurs after the age of 3 years. Diseases of the nervous system and other medical conditions associated with regression (e.g. acquired epileptic aphasia or Landau-Kleffner syndrome, autoimmune encephalitis, Rett syndrome) are differentiated from autism spectrum disorder with loss of previously acquired skills on the basis of an early history of relatively normal social and language development, and by the characteristic neurological features of these disorders that are not typical of autism spectrum disorder. Boundary with secondary neurodevelopmental syndrome Autistic features may become manifest in the context of acquired medical conditions, such as encephalitis. Identifying accurately whether the symptoms are secondary to another medical condition or represent the exacerbation of pre-existing autism spectrum disorder may have implications for both immediate management and prognosis. When autistic symptoms are attributable to another medical condition, a diagnosis of secondary neurodevelopmental syndrome rather than autism spectrum disorder may be assigned. Developmental learning disorder Essential (required) features • The presence of significant limitations in learning academic skills of reading, writing or arithmetic, resulting in a skill level markedly below what would be expected based on age is required for diagnosis. Limitations in learning are manifest, despite appropriate academic instruction in the relevant areas. The limitations may be restricted to a single component of a skill (e.g. an inability to master basic numeracy, or to decode single words accurately and fluently) or may affect all reading, writing and arithmetic. Ideally, limitations are measured using appropriately normed and standardized tests. • Onset of the limitations typically occurs during the early school years, but in some individuals may not be identified until later in life, including into adulthood, when performance demands related to learning exceed limited capacities. • The limitations are not attributable to external factors, such as economic or environmental disadvantage, or lack of access to educational opportunities. • The learning difficulties are not better accounted for by a disorder of intellectual development or another neurodevelopmental disorder, or by another condition such as a motor disorder or a sensory disorder of vision or hearing. • The learning difficulties result in significant impairment in the individual’s academic, occupational or other important areas of functioning. If functioning is maintained, it is only through significant additional effort. 6A03 Neurodevelopmental disorders | Developmental learning disorder

135 Neurodevelopmental disorders Specifiers for area of learning impairment Specifiers should be applied to indicate which academic skills are significantly impaired at the time of assessment. Multiple specifiers may be used to reflect limitations in multiple skills. Impairment in reading • Learning difficulties are manifested in impairments in reading skills such as word reading accuracy, reading fluency or reading comprehension. Impairment in written expression • Learning difficulties are manifested in impairments in writing skills such as spelling accuracy, grammar and punctuation accuracy, or organization and cohesion of ideas in writing. Impairment in mathematics • Learning difficulties are manifested in impairments in mathematical skills such as number sense, memorization of number facts, accurate calculation, fluent calculation or accurate mathematic reasoning. Other specified impairment of learning • Learning difficulties are manifested in impairments in learning and performance of specific academic skills that are not adequately characterized by one of the other available specifiers. Developmental learning disorder, unspecified 6A03.0 6A03.1 6A03.2 6A03.3 6A03.Z Neurodevelopmental disorders | Developmental learning disorder

Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural or Neurodevelopmental Disorders Additional clinical features • Individuals with developmental learning disorder typically show impairments in various underlying psychological processes that may include phonological processing, orthographic processing, memory (including working memory), executive functions (including inhibitory control, set-shifting, planning), learning and automatizing symbols (e.g. visual, alphanumeric), perceptual-motor integration and speed of processing information. Deficits in these psychological processes are presumed to underlie a child’s ability to learn academic skills. However, the precise relationship between psychological processes and outcomes related to learning capacity is not yet sufficiently understood to allow an accurate and clinically useful classification based on these underlying processes. • Developmental learning disorder commonly co-occurs with other neurodevelopmental disorders, such as attention deficit hyperactivity disorder, developmental motor coordination disorder, developmental language disorder and autism spectrum disorder. • Many individuals with developmental learning disorder have marked difficulties selfregulating attention that are not sufficiently severe to warrant a separate diagnosis. Persistent difficulties with self-regulated attention can have deleterious effects on academic outcomes, and may impede response to intervention or support. • Some individuals with developmental learning disorder may be able to sustain seemingly adequate levels of key academic skills by using compensatory strategies or through devoting extraordinarily high levels of effort or time, or through the provision of unusually high levels of support. However, as demands for efficiency in key academic skills increase and exceed capabilities (e.g. in timed tests, reading or writing lengthy detailed reports for a tight deadline, heavier academic coursework as in high school/secondary school, postsecondary education or professional training), the underlying learning difficulties tend to become more fully apparent. • Ideally, determination of the presence of developmental learning disorder includes assessment of academic achievement using standardized, appropriately normed instruments. However, a child’s score on a single test measuring a particular academic skill is not sufficient to distinguish disorder from normality. Achievement scores may vary as a result of the technical properties of the specific test being used, the testing conditions and a variety of other variables, and also can vary substantially over the individual’s development and life-course. Therefore, the diagnosis of developmental learning disorder should also consider various sources of evidence regarding the child’s capacity for learning outside the formal testing situation. Boundary with normality (threshold) • The age of acquisition of academic skills varies, and later acquisition of a particular academic skill compared to same-age peers does not necessarily indicate the presence of a disorder. Developmental learning disorder is distinguished by persistent difficulty in learning the particular academic skills over time in spite of adequate educational opportunities, and by the severity of the impairment caused by the learning difficulty. Neurodevelopmental disorders | Developmental learning disorder

137 Neurodevelopmental disorders Course features • Deficits in reading, mathematics and written expression identified in childhood typically persist through adolescence and into adulthood. These deficits may negatively affect a child’s academic achievement, increase the likelihood of school dropout, and contribute to unemployment (or underemployment) in adulthood – particularly if left untreated. Along with school dropout, significant co-occurring depressive symptoms increase the risk of poor mental health outcomes, including suicide. • The specific impairments associated with developmental learning disorder vary with developmental stage and learning abilities, severity of deficits, complexity of tasks, presence of co-occurring mental, behavioural and neurodevelopmental disorders, and the availability of support. • Developmental learning disorder is also associated with heightened risk of suicidal ideation and suicide attempts across the lifespan. Developmental presentations • Developmental learning disorder is most often diagnosed during elementary school years because difficulties in reading, mathematics and/or writing typically only become evident when these topics are taught formally. Some individuals, however, may not be diagnosed until later in development, including in adulthood. Premorbid impairments, such as in language, counting or rhyming, or fine motor control tend to be evident in early childhood prior to the diagnosis of developmental learning disorder. • The prevalence of developmental learning disorder across all areas of impairment (i.e. reading, written expression and mathematics) is estimated to affect between 5% and 15% of school-aged children. Prevalence among adults is unknown, but is estimated at approximately 4%. The prevalence of developmental learning disorder for specific academic areas among school-aged children is variable (reading is estimated at 5–17%; mathematics at 6–7%; written expression at 7–15%). • Children with developmental learning disorder frequently exhibit co-occurring symptoms of depressive disorders, anxiety and fear-related disorders, and externalizing behaviour disorders, which may make it more difficult to assess their learning impairments. • Children with developmental learning disorder with impairment in one academic area are more likely to have co-occurring impairments in other areas. Culture-related features • Developmental learning disorder with impairment in reading can be manifested differently by language. For example, in English, the presentation involves inaccurate and slow reading of single words. In other languages with more direct mapping between sounds and letters (e.g. Spanish, German) and non-alphabetic languages (e.g. Chinese, Japanese), the typical presentation is slow but accurate reading. Neurodevelopmental disorders | Developmental learning disorder

Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural or Neurodevelopmental Disorders Sex- and/or gender-related features • Developmental learning disorder is more common among boys. Boys may be more likely to be clinically referred because of greater prevalence of co-occurring attention deficit hyperactivity disorder or problematic externalizing behaviours. • Among community samples, the gender ratio of males to females ranges from 1.5:1 to 3:1. This ratio appears greater in clinical samples (estimated at 6:1). Boundaries with other disorders and conditions (differential diagnosis) Boundary with disorders of intellectual development Individuals with disorders of intellectual development often present with limitations in academic achievement by virtue of significant generalized deficits in intellectual functioning. It is therefore difficult to establish the co-occurring presence of a developmental learning disorder in individuals with a disorder of intellectual development. Developmental learning disorder should only be diagnosed in the presence of a disorder of intellectual development when the limitations in learning are significantly in excess of those usually expected for the individual’s level of intellectual functioning. Boundary with developmental language disorder Persistent deficits in the acquisition, understanding, production or use of language in developmental language disorder may lead to academic learning difficulties, especially in literacy – including word reading and written output. If all diagnostic requirements for both developmental language disorder and developmental learning disorder are met, both diagnoses may be assigned. Boundary with attention deficit hyperactivity disorder Many individuals with developmental learning disorder have marked difficulties in self-regulating attention. However, unlike in attention deficit hyperactivity disorder, the limitations in acquisition of academic skills in developmental learning disorder are not solely a function of a child’s ability to sustain attention on academic tasks or modulate their activity level appropriately. The co-occurrence of developmental learning disorder and attention deficit hyperactivity disorder is common, and both disorders may be diagnosed if diagnostic requirements are met. Boundary with sensory impairments Developmental learning disorder must be differentiated from learning difficulties that arise because of sensory impairments in vision or hearing. However, individuals with vision and hearing problems for which appropriate accommodations have been made may also have co-occurring developmental learning disorder. Boundary with neurodegenerative diseases Developmental learning disorder is distinguished from learning difficulties that occur after the developmental period due to neurodegenerative diseases or to injury (e.g. traumatic brain injury) by the fact that in the latter conditions there is a loss of previously acquired academic skills and previous capacity for learning new skills. Neurodevelopmental disorders | Developmental learning disorder