Developmental language disorder (DLD) is identified when a child has problems with language development that continue into school age and beyond. The language problems have a significant impact on everyday social interactions or educational progress, and occur in the absence of autism spectrum disorder, intellectual disability or a known biomedical condition. The most obvious problems are difficulties in using words and sentences to express meanings, but for many children, understanding of language (receptive language) is also a challenge. This may not be evident unless the child is given a formal assessment. Classification
Terminology
The term developmental language disorder (DLD) was endorsed in a consensus study involving a panel of experts (CATALISE Consortium) in 2017. The study was conducted in response to concerns that a wide range of terminology was used in this area, with the consequence that there was poor communication, lack of public recognition, and in some cases children were denied access to services. Developmental language disorder is a subset of language disorder, which is itself a subset of the broader category of speech, language and communication needs (SLCN). The terminology for childrens language disorders has been extremely wide-ranging and confusing, with many labels that have overlapping but not necessarily identical meanings. In part this confusion reflected uncertainty about the boundaries of DLD, and the existence of different subtypes. Historically, the terms "developmental dysphasia" or "developmental aphasia" were used to describe children with the clinical picture of DLD. These terms have, however, largely been abandoned, as they suggest parallels with adult-acquired aphasia.
There are three points that need to be met for a diagnosis of DLD:
The child has language difficulties that create obstacles to communication or learning in everyday life,
The childs language problems are unlikely to resolve by five years of age, and
The problems are not associated with a known biomedical condition such as brain injury, neurodegenerative conditions, genetic conditions or chromosome disorders such as Down syndrome, sensorineural hearing loss, autism spectrum disorder, or intellectual disability.For research and epidemiological purposes, specific cutoffs on language assessments have been used to document the first criterion. Tomblin et al. proposed the EpiSLI criterion, based on five composite scores representing performance in three domains of language (vocabulary, grammar, and narration) and two modalities (comprehension and production). Children scoring in the lowest 10% on two or more composite scores are identified as having language disorder. The second criterion, persistence of language problems, can be difficult to judge in a young child, but longitudinal studies have shown that difficulties are less likely to resolve for children who have poor language comprehension, rather than difficulties confined to expressive language. In addition, children with isolated difficulties in just one of the areas noted under subtypes tend to make better progress than those whose language is impaired in several areas.The third criterion specifies that DLD is used for children whose language disorder is not part of another biomedical condition, such as a genetic syndrome, a sensorineural hearing loss, neurological disease, autism spectrum disorder or intellectual disability – these were termed differentiating conditions by the CATALISE panel.