Expressive language delay is one of the most common reasons children are referred to speech-language pathology. Whether it's a toddler with a small vocabulary, a preschooler who speaks in single words when their peers use sentences, or a school-age child whose written and oral expression lags behind their comprehension, expressive language delays span a wide range of profiles and require careful assessment to identify the right targets and approach.
Late Talkers vs. Language Impairment: An Important Distinction
Not all children who talk late have a language impairment. Research by Paul (1996) and others identified a group of children—"late talkers"—who present with expressive vocabulary delays in the toddler years but catch up to peers without intervention by age 4–5. Approximately 50–70% of late talkers resolve without treatment.
However, children who are "late bloomers" cannot be reliably identified prospectively—you can't know which late talker will catch up until they do or don't. Risk factors for persistent language impairment include: limited vocabulary at 24 months (fewer than 50 words), absent or minimal word combinations by 24–30 months, positive family history of language disorder, limited receptive language skills, and limited symbolic play. When multiple risk factors are present, early intervention is warranted rather than a "wait and see" approach.
Language impairment (also called Developmental Language Disorder, or DLD) is a persistent condition—not a delay that will self-resolve. DLD affects approximately 7% of children and is characterized by difficulties with both receptive and expressive language that persist through school years and into adulthood. Children with DLD need ongoing, targeted intervention.
Assessment of Expressive Language
A comprehensive expressive language assessment includes standardized testing, language sampling, and observation across contexts:
Mean Length of Utterance (MLU): Calculated from a 50–100 utterance spontaneous language sample. MLU in morphemes is a robust and sensitive measure of expressive language development through approximately age 5. Brown's (1973) stages of language development provide normative reference points: Stage I (MLU 1.0–2.0), Stage V+ (MLU 3.75+).
Standardized Tests: The Clinical Evaluation of Language Fundamentals (CELF-5) includes expressive subscales (Formulated Sentences, Recalling Sentences, Word Definitions) and provides age-referenced standard scores. The Expressive One Word Picture Vocabulary Test (EOWPVT-4) provides a standardized measure of expressive vocabulary. For younger children, the Preschool Language Scales (PLS-5) captures both expressive and receptive skills.
Language Samples: Standardized samples (e.g., using the SALT software norms) provide data on sentence length, syntactic complexity, semantic diversity, and narrative structure. Language samples are essential—standardized tests alone miss the nuances of how children use language in natural contexts.
Evidence-Based Treatment Approaches
Milieu Teaching: An embedded, naturalistic approach in which language targets are taught during meaningful activities and routines. The SLP (or parent, after training) creates opportunities for communication, waits for the child to attempt, prompts if needed, and responds contingently. Milieu teaching is particularly effective for early vocabulary and early sentence production in toddlers and preschoolers. Variants include Enhanced Milieu Teaching (EMT) and Prelinguistic Milieu Teaching (PLT) for pre-verbal children.
Recasting: Following the child's utterance with a more complex or grammatically complete version of the same idea. If the child says "doggy run," the SLP recasts: "Yes, the dog is running!" Recasting provides implicit corrective feedback without direct correction and has strong evidence for improving grammatical morphology and sentence structure.
Modeling / Focused Stimulation: The SLP models target structures repeatedly within meaningful contexts without requiring imitation from the child. For a child who is not using verb tenses, the SLP might spend 15 minutes narrating activities using past tense: "We painted. He jumped. She sang." Focused stimulation increases input of the target structure and improves production over time.
Script Therapy: For children who need structured language in specific contexts (academic routines, social exchanges), script therapy teaches a set of repeated utterances in predictable situations. Useful for school-age children with autism or DLD who struggle with formulaic language.
Intervention Targets by Age
- 12–18 months: First words, communicative intent, joint attention, early vocabulary (objects, actions, social words).
- 18–24 months: Vocabulary expansion (50+ words), early word combinations, requesting, labeling, protesting.
- 2–3 years: Two- to three-word phrases, Brown's morphemes (present progressive, plurals, possessives), simple questions.
- 3–5 years: Complex sentences, irregular past tense, pronouns, narrative skills, metalinguistic awareness.
- School age: Complex syntax (relative clauses, passives), inferential language, academic vocabulary, narrative macrostructure (story grammar), classroom discourse.
Working with English Language Learners
Language differences and language disorders are distinct, and misidentifying ELL students as having a language disorder is a significant equity issue. ELL children may have reduced vocabulary in English that does not reflect their true language capacity. Assessment must include information about both languages, ideally using bilingual norms or dynamic assessment that evaluates the child's ability to learn, not just their current performance.
Key principle: a true language disorder is present in both languages. If a child has rich vocabulary and complex syntax in their home language but limited English, the issue is English language acquisition, not a language disorder. Collaborate with bilingual educators and interpreters to gather accurate cross-language information.
Parent Coaching
For young children, parent-implemented intervention is often more powerful than direct SLP services alone because parents have far more interaction time with the child each day. Teaching parents responsive interaction strategies—following the child's lead, expanding utterances, reducing questions, creating communication temptations—multiplies intervention exposure dramatically.
SLPDesk's language activity library includes parent-facing activity guides for common expressive language targets, making it easy to send home structured practice that aligns with what you're targeting in sessions.