Reading and Math Achievement in Children With Dyslexia, Developmental Language Disorder, or Typical Development: Achievement Gaps Persist From Second Through Fourth Grades.

We examined how children (N = 448) with separate or co-occurring developmental language disorder (DLD) and dyslexia performed on school-based measures of academic functioning between second and fourth grades. Children were recruited from 1 school district in the U.S. state of South Carolina via classroom screenings and met common research criteria for DLD and dyslexia. Growth curve models were used to examine the overall form of growth and differences between groups. Children with DLD and/or dyslexia in second grade showed early and persistent deficits on school-administered measures of reading and math. In second grade, children with typical development (TD) scored significantly higher than children with dyslexia-only and DLD-only, who did not differ from each other. Children with DLD+dyslexia scored significantly lower than all other groups. Only small differences in growth rates were observed, and gaps in second grade did not close. Despite lower academic performance, few children (20%-27%) with dyslexia and/or DLD had received specialized support services. Children with DLD-only received services at less than half the rate of dyslexia-only or DLD+dyslexia despite similar impacts on academic performance. Evidence of significant and persistent functional impacts in the context of low rates of support services in these children-especially those with DLD-only-highlights the need to raise awareness of these disorders.

Examining the Associations Between Parent Concerns and School-Age Children's Language and Reading Abilities: A Comparison of Samples Recruited for In-School Versus Online Participation.

PURPOSE: The purpose of this study was to examine the relationship between parent concerns about children's oral language, reading, and related skills and their children's performance on standardized assessments of language and reading, with a particular focus on whether those relationships differed between children recruited for in-school versus online participation. METHOD: This study used data from a larger, longitudinal project focused on children with and without developmental language disorder (DLD) and/or dyslexia. The "in-school" sample (n = 133) completed assessments in-person before school closures, and the "online" sample (n = 84) recruited via advertisements completed assessments online. Parents completed a checklist of concerns. All children completed norm-referenced assessments of language and reading. RESULTS: The two recruitment strategies yielded samples that differed in racial diversity (higher in the in-school sample), caregiver education levels (higher in the online sample), and word reading test scores (higher in the online sample). Parents in both samples reported higher levels of concerns about literacy skills than oral language skills, and the correlation between parent concerns about literacy and children's word reading test scores was stronger than the correlation between parent concerns about oral language and children's language test scores. CONCLUSIONS: Researchers and clinicians should be aware of how recruitment strategies and assessment modalities (e.g., in-person vs. tele-assessment) may impact participation in studies and clinical service. A reliance on parent concerns about oral language to prompt a language evaluation may contribute to low rates of identification of children who meet criteria for DLD. Future research can consider parent concerns about literacy, attention, and executive functions as indicators of a need for language evaluation, especially considering the high comorbidity between language and other developmental disorders.

Has Vocabulary Intervention Had an Effect? A Valid, Reliable, and (Fairly) Quick Outcome Measure for Semantic Knowledge.

Purpose Vocabulary intervention should be guided by information from outcome measures that demonstrate whether the student has grown in depth or breadth of understanding of the taught words. However, there is a paucity of tools, to measure depth of vocabulary knowledge, that are available for clinical use. Method The challenges of vocabulary measurement are summarized. A procedure to assess semantic knowledge of specific words, both before and after treatment, is outlined: 5 yes/no questions that use the target word in different contexts (Stallman et al., 1995), and definitions, scored on a 5-point scale (Duff, 2019). These combined measures evaluate word knowledge along a wide continuum of semantic knowledge. Results Evidence for the validity and reliability of these measures, as well as sensitivity to treatment effects, is reviewed, and implementation resources are provided for clinicians. Conclusion This protocol can be used by clinicians to evaluate the effectiveness of vocabulary treatment by comparing a child's semantic knowledge of specific words before and after treatment.

The Effect of Vocabulary Intervention on Text Comprehension: Who Benefits?

Purpose Vocabulary intervention can improve comprehension of texts containing taught words, but it is unclear if all middle school readers get this benefit. This study tests 2 hypotheses about variables that predict response to vocabulary treatment on text comprehension: gains in vocabulary knowledge due to treatment and pretreatment reading comprehension scores. Method Students in Grade 6 (N = 23) completed a 5-session intervention based on robust vocabulary instruction (RVI). Knowledge of the semantics of taught words was measured pre- and posttreatment. Participants then read 2 matched texts, 1 containing taught words (treated) and 1 not (untreated). Treated texts and taught word lists were counterbalanced across participants. The difference between text comprehension scores in treated and untreated conditions was taken as a measure of the effect of RVI on text comprehension. Results RVI resulted in significant gains in knowledge of taught words (dRM = 2.26) and text comprehension (dRM = 0.31). The extent of gains in vocabulary knowledge after vocabulary treatment did not predict the effect of RVI on comprehension of texts. However, untreated reading comprehension scores moderated the effect of the vocabulary treatment on text comprehension: Lower reading comprehension was associated with greater gains in text comprehension. Readers with comprehension scores below the mean experienced large gains in comprehension, but those with average/above average reading comprehension scores did not. Conclusion Vocabulary instruction had a larger effect on text comprehension for readers in Grade 6 who had lower untreated reading comprehension scores. In contrast, the amount that children learned about taught vocabulary did not predict the effect of vocabulary instruction on text comprehension. This has implications for the identification of 6th-grade students who would benefit from classroom instruction or clinical intervention targeting vocabulary knowledge.

The Influence of Reading on Vocabulary Growth: A Case for a Matthew Effect.

PURPOSE: Individual differences in vocabulary development may affect academic or social opportunities. It has been proposed that individual differences in word reading could affect the rate of vocabulary growth, mediated by the amount of reading experience, a process referred to as a Matthew effect (Stanovich, 1986). METHOD: In the current study, assessments of written word-reading skills in the 4th grade and oral vocabulary knowledge collected in kindergarten and in the 4th, 8th, and 10th grades from a large epidemiologically based sample (n = 485) allowed a test of the relationship of early word-reading skills and the subsequent rate of vocabulary growth. RESULTS: Consistent with the hypothesis, multilevel modeling revealed the rate of vocabulary growth after the 4th grade to be significantly related to 4th-grade word reading after controlling for kindergarten vocabulary level, that is, above average readers experienced a higher rate of vocabulary growth than did average readers. CONCLUSIONS: Vocabulary growth rate differences accumulated over time such that the effect on vocabulary size was large.

Children with developmental language impairment have vocabulary deficits characterized by limited breadth and depth.

BACKGROUND: Deficient vocabulary is a frequently reported symptom of developmental language impairment, but the nature of the deficit and its developmental course are not well documented. AIMS: To describe the nature of the deficit in terms of breadth and depth of vocabulary knowledge and to determine whether the nature and the extent of the deficit change over the school years. METHODS & PROCEDURES: A total of 25 681 oral definitions produced by 177 children with developmental language impairment (LI) and 325 grade-mates with normally developing language (ND) in grades 2, 4, 8 and 10 were taken from an existing longitudinal database. We analysed these for breadth by counting the number of words defined correctly and for depth by determining the amount of information in each correct definition. Via a linear mixed model, we determined whether breadth and depth varied with language diagnosis independent of non-verbal IQ, mothers' education level, race, gender, income and (for depth only) word. OUTCOMES & RESULTS: Children with LI scored significantly lower than children with ND on breadth and depth of vocabulary knowledge in all grades. The extent of the deficit did not vary significantly across grades. Language diagnosis was an independent predictor of breadth and depth and as strong a predictor as maternal education. For the LI group, growth in depth relative to breadth was slower than for the ND group. CONCLUSIONS & IMPLICATIONS: Compared with their grade-mates, children with LI have fewer words in their vocabularies and they have shallower knowledge of the words that are in their vocabularies. This deficit persists over developmental time.

Associations between syntax and the lexicon among children with or without ASD and language impairment.

Five groups of children defined by presence or absence of syntactic deficits and autism spectrum disorders (ASD) took vocabulary tests and provided sentences, definitions, and word associations. Children with ASD who were free of syntactic deficits demonstrated age-appropriate word knowledge. Children with ASD plus concomitant syntactic language impairments (ASDLI) performed similarly to peers with specific language impairment (SLI) and both demonstrated sparse lexicons characterized by partial word knowledge and immature knowledge of word-to-word relationships. This behavioral overlap speaks to the robustness of the syntax-lexicon interface and points to a similarity in the ASDLI and SLI phenotypes.