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. Language disorders occurring with these conditions need to be assessed and children offered appropriate intervention, but a terminological distinction is made so that these cases would be diagnosed as language disorder associated with the main diagnosis being specified: e.g. "language disorder associated with autism spectrum disorder." The reasoning behind these diagnostic distinctions is discussed further by Bishop (2017). Benchmarks for children with developmental language disorder Common red flags at one year of age: No reaction to sound No babbling Difficulty feeding No imitation Limited use of gestures At two years of age: Makes minimal attempts to communicate with gestures or words Has not spoken their first words Difficulty following simple directions Inconsistent response to "no" At three years of age: Limited use of speech Incomprehensible speech Limited understanding of simple questions Difficulty naming objects Frustration related to communication At four years of age: Uses only 3-word phrases Speech is not understandable to parents Takes a long time to understand others Difficulty asking questions and finding words to express thoughts At five years of age: Speaks only in simple sentences Speech is not understandable to teachers Difficulty answering questions Difficulty with complex directions Difficulty telling stories Difficulty with peer interactions Assessment Assessment will usually include an