Accelerating Word Learning in Children With Language Impairment

This research attempts to adapt and optimize a word learning treatment, specifically interactive book reading, for use with Kindergarten children with Specific Language Impairment (SLI). Children with SLI have difficulty learning language without any obvious cause for this difficulty. This study will examine the best way to achieve the appropriate intensity of 36 exposures. For example, is it better to hear the new words many times within the book (high dose) and to read the book few times (low dose frequency), or is it better to hear the new words a few times within the book (low dose) and to read the book many times (high dose frequency). The investigators hypothesize that reading the books many times will be more effective than repeating the words many times within a book.

Specific Language Impairment (SLI) affects approximately 7.4% of Kindergarten children. Children with SLI are known to have difficulty learning new words, which places them at greater risk for future reading impairments and academic failure. Surprisingly, there are few interventions for word learning by children with SLI that have undergone rigorous efficacy and/or effectiveness testing. The goal of this research is to optimize an interactive book reading intervention that has proven to be successful in teaching vocabulary to other groups of Kindergarten children. A secondary goal was to examine whether pre-treatment characteristics predicted how many words children would learn. This study further tests the adequate intensity of 36 exposures. Each child will receive two treatments at the identified adequate intensity. Children were randomized to two treatments: the standard treatment and 1 of 2 alternative treatments. The standard treatment used in prior research was balanced between the amount of times the new word is heard within the book (dose 6) and the amount of times the book is read (dose frequency 6). The alternative treatments were more heavily weighted for either repetitions within the book (high dose/low dose frequency, i.e., dose 9 x dose frequency 4) or the amount of times the book is read (low dose/high dose frequency, i.e., dose 4 x dose frequency 9). Ultimately, this study determines how best to achieve the adequate intensity of 36 exposures. A secondary goal was to further examine the pre-treatment factors associated with the number of words learned by children with SLI during interactive book reading. We once again explore a variety of potential predictors including those that were significant in a prior study (i.e., phonological awareness, nonword repetition, and semantics) as well as those that were not significant in a prior study but that had the potential to be related to a child's ability to learn during interactive book reading. That is, a child's general language abilities (as measured by the Clinical Evaluation of Language Fundamentals-4, CELF-4, Core Language score) and their ability to understand verbally presented stories (as measured by the CELF-4 Understanding Spoken Paragraphs score) could impact their success in encoding new words during interactive book reading.

Children in this arm are assigned to the standard treatment for the first round of intervention (dose 6 x dose frequency 6) and then the alternative treatment that maximizes dose (dose 9 x dose frequency 4)

Children in this arm are assigned to the alternative treatment that maximizes dose (dose 9 x dose frequency 4) in the first round of intervention and then to the standard treatment for the second round of intervention (dose 6 x dose frequency 6)

Children in this arm are assigned to the alternative treatment that maximizes dose frequency (dose 4 x dose frequency 9) in the first round of intervention and then to the standard treatment for the second round of intervention (dose 6 x dose frequency 6)

Children in this arm are assigned to the standard treatment for the first round of intervention (dose 6 x dose frequency 6) and then the alternative treatment that maximizes dose frequency (dose 4 x dose frequency 9)

Children receive 2 rounds of treatment with interactive book reading. Each treatment teaches 30 words that the children do not know. Treatments vary in dose (the number of times the words is heard/taught in an individual book reading session: 4 vs. 6 vs. 9) and dose frequency (the number of times book reading sessions are repeated: 4 vs. 6. vs. 9). Across all dose x dose frequency combinations, children hear/are taught the 30 words 36 times, which has been shown to be the adequate overall intensity of the intervention.

In each of the two treatments, children are taught 30 new words and tested on their ability to provide a definition of each word. Definitions are scored as 0 points for an incorrect or absent definition, 1 point for an appropriate use of the word in a sentence or for a vague definition, 2 points for a conventional definition containing at least one critical element but lacking other critical elements, and 3 points for a complete and accurate definition including all critical elements. For the analyses, children's definitions scored as 2 or 3 (i.e., a partially or completely accurate definition) were counted as correct (i.e., the child knows the word) and definitions scored as 0 or 1 (i.e., incorrect definition, absent definition, correct use of a word in a sentence, or vague definition) were counted as incorrect (i.e., the child does not know the word). Thus, children's scores could range from 0 to 30 words known, with higher scores indicating better outcomes.

Learning also was tracked during treatment. The research assistant who provided the treatment prompted children to provide definitions at four points during each treatment. Depending on the arm, the four test points corresponded to 6-9 exposures, 18-20 exposures, 27-30 exposures, and 36 exposures.The words were assessed in a fixed order while the child viewed the pre-reading pictures for each word. The research assistant asked, "What does [word] mean?". Specific feedback was not provided but the correct definition always was provided after the child's response regardless of the accuracy of the response. Scoring was the same as that described for definitions administered pre/post. Scores could range from 0-30 words correctly defined.

Learning also was tracked during treatment. The research assistant who provided the treatment prompted children to name the target words at four points during each treatment. Depending on the arm, the four test points corresponded to 6-9 exposures, 18-20 exposures, 27-30 exposures, and 36 exposures. The research assistant showed the child the post-book reading picture without the orthographic label and asked a question meant to elicit the phonological form of the target word (e.g., "What is the lightning doing?" to elicit flashing). Specific feedback was not provided but the correct orthographic label and context sentence always were provided after the child's response regardless of the accuracy of the response. Responses were scored as correct (i.e., matched the target word) or incorrect (i.e., did not match the target word). Total score could range from 0 to 30 words correctly named in each treatment.

Inclusion Criteria: Eligible for Kindergarten enrollment Age 5 to 6 years Normal hearing Nonverbal Intelligence Quotient (IQ) of 85 or higher on the Reynolds Intellectual Assessment Scale Score below 82 on the Clinical Evaluation of Language Fundamentals Score at or below the 10% percentile on one of the approved standardized vocabulary assessments. Exclusion Criteria: Speaks more than one language Health history indicating neurologic or other disorder that would exclude a diagnosis of SLI (e.g., autism, developmental disability, seizure disorder)