There are 3 words in the term, Developmental Language Disorder.
Developmental means that the condition starts over the course of development. Developmental Language Disorder (DLD) is not acquired or associated with a known biomedical cause. As developmental problem, DLD means that the child is not able to develop language as expected, and so the child is not expected to ‘grow out of’ the condition.
Language refers to the system of words and symbols that convey meaning through talking, gesture, or writing. Children learn language at their own pace, with the greatest change usually occurring in the first three years of life. By the time a child is 5 years old, they are usually speaking and understanding sentences.
Disorder is the most difficult of these words to understand. In medical terms, disorder refers to a disturbance of normal functioning of the mind or body. Sometimes, a disorder is caused by a specific genetic factor, disease, or trauma, which can make determining the presence of the condition more straight forward. DLD, however, is a spectrum disorder with multiple contributors rather than any one clear cause. This complexity can make DLD difficult to diagnose.
The presence of a disorder in the development of language (i.e., DLD) is determined based on the presence of characteristic symptoms or behaviors in a child, typically after some responsible adult has raised concerns. The problem is that there is no set point that divides those with and without a language disorder. A speech-language pathologist (SLP) must draw on multiple sources of information to determine if a child has DLD.
Determining the Presence of DLD
Here are some sources of information an SLP might use to determine the presence of DLD:
- Cut-points on a standardized language test: An SLP might administer a language test to determine if the child scores in a very different way from other children their age. Even still, test scores alone don’t determine the presence of DLD. A child could score low on a language test for other reasons, and so more information is needed. Read more about standardized scores here .
- Information about the child’s general development: Parents will be asked about the child’s development. If concerns arise in other areas of the child’s development, other assessments might be completed to determine if another condition is present.
- Information about the child’s language context: It will be important to consider the child’s language skills in all the languages the child is learning. If the child is learning at least one language without difficulty, then DLD would be ruled out.
- Information about the child’s learning: Teachers or others providing intervention to the child will be asked about the child’s learning. A child with DLD would likely have trouble learning even when additional help is provided.
- Observation: The SLP will spend time observing the child’s natural communication in conversations with one or more people. Observing the child’s everyday communication skills can really help determine how much the child is struggling with language.
DLD is diagnosed  when the assessment findings indicate persistent language difficulties with a significant impact on everyday interactions and/or school learning (and in the absence of any associated biomedical condition). The term ‘disorder’ can seem scary, but it is meant to recognize both the seriousness and importance of the language difficulties. DLD also signals neurodiversity in language learning and processing, and the need to identify the particular strategies most beneficial to supporting this individual with DLD.
- Bishop, D. V. M., Snowling, M. J., Thompson, P. A., Greenhalgh, T., & the CATALISE-2 consortium. (2017). CATALISE: A multinational and multidisciplinary Delphi consensus study of problems with language development. Phase 2. Terminology. Journal of Child Psychology and Psychiatry, 58:10, 1068-1080.