The number of unique words in children's speech is one of most basic statistics indicating their language development. We may, however, face difficulties when trying to accurately evaluate the number of unique words in a child's growing corpus over time with a limited sample size. This study proposes a novel technique to estimate the latent number…

Communicative Development Inventories (CDIs, parent-completed language development checklists) are a helpful tool to assess language in children who are unused to interaction with unfamiliar adults. Generally, CDIs are completed in written form, but in developing country settings parents may have insufficient literacy to complete them alone. We…

Parent report has proven a valid and cost-effective means of evaluating early child language. Norming datasets for these instruments, which provide the basis for standardized comparisons of individual children to a population, can also be used to derive norms for the acquisition of individual words in production and comprehension and also early…

Numerous studies show that children's language ability is related to false-belief understanding. However, there is considerable variation in the size of the correlation reported. Using data from 104 studies (N=8,891), this meta-analysis determines the strength of the relation in children under age 7 and examines moderators that may account for the…

Six children were studied from the age of 6 months to 1 year and 6 months to chart their developing comprehension vocabularies from the first to the 100th word. Observational data were used in the first instance to identify newly comprehended words and then controlled testing was carried out for each word to confirm and expand the observational…

Production of the deictic verbs "bring" and "take" was evaluated among 88 normally functioning elementary school children. Results showed that data evaluation procedures greatly influenced conclusions, the second-to-emerge form was easier to learn in a conventional way, and the second term was the proactive stimulus for…

Analysis of data from studies investigating the effectiveness of a parent report form for assessing children's early language development showed that the vocabulary checklist had substantial validity, and that it helped parents to provide a valuable overall evaluation of their children's language at 20 months. (Author/CB)