<unk>  is defined purely in behavioural terms: there is no biological test for<unk> . There are three points that need to be met for a diagnosis of<unk> : * The child has language difficulties that interfere with daily life or academic progress * Other causes are excluded: the problems cannot be explained in terms of hearing loss, general developmental delay, autism, or physical difficulty in speaking * Performance on a standardized language test (see assessment, below) is significantly below age level There is considerable variation in how this last criterion is implemented. Tombin et al. (1996) 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. Assessment Assessment will usually include an interview with the child's caregiver, observation of the child in an unstructured setting, a hearing test, and standardized tests of language and nonverbal ability. There is a wide range of language assessments in English. Some are restricted for use by speech and language professionals (therapists or SALTs in the UK, speech-language pathologists, SLPs, in the US and Australia). A commonly used test battery for diagnosis of<unk>  is the Clinical Evaluation of Language Fundamentals (CELF). Assessments that can be completed by a parent or teacher can be useful to identify children who may require more in-depth evaluation. The Grammar and Phonology Screening (GAPS) test is a quick (ten minute) simple and accurate screening test developed and standardized in the UK. It is suitable for children from 3;4 to 6;8 years;months and can be administered by professionals and non-professionals (including parents) alike, and has been demonstrated to be highly accurate (98% accuracy) in identifying impaired children who need specialist help vs non-impaired children. This makes it potentially a feasible test for widespread screening. The Children’s Communication Checklist (CCC–2) is a parent questionnaire suitable for testing language skills in school-aged children. Informal assessments, such as language samples, may also be used. This procedure is useful when the normative sample of a given test is inappropriate for a given child, for instance, if the child is bilingual and the sample was of monolingual children. It is also an ecologically valid measure of all aspects of language (e.g. semantics, syntax, pragmatics, etc.). To complete a language sample, the SLP will spend about 15 minutes talking with the child. The sample may be of a conversation (Hadley, 1998), or narrative retell. In a narrative language sample, the SLP will tell the child a story using a wordless picture book (e.g. Frog Where Are You?, Mayer, 1969), then ask the child to use the pictures and tell the story back. Language samples are typically transcribed using computer software such as the systematic analysis of language software (SALT, Miller et al. 2012), and then analyzed. For example, the SLP might look for whether the child introduces characters to their story or jumps right in, whether the events follow a logical order, and whether the narrative includes a main idea or theme and supporting details.
Specific language impairment
Nonverbal learning disorder
Language delay
Mixed receptive-expressive language disorder
Global perceptions of autism
Speech and language impairment
Language disorder
Global developmental delay