The Effect of Prior Learning on Word Learning

Study Overview
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Brief Summary
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The goal of this clinical trial is to compare two treatment conditions for late talking toddlers. In 8 weeks of word learning treatment, toddlers will be taught words that sound more like the words they already know or sound less like the words they already know. The investigators see which group learns more, to understand if choosing words that let children use the knowledge they already have helps with learning.

Detailed Description
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Late talking toddlers will be assigned to be in the More Familiar Sounds condition or the Less Familiar Sounds condition. Both groups will receive 8 weeks of Vocabulary Acquisition and Usage for Late Talkers (VAULT) word learning treatment (2x/week for 30 minutes per session) using their words. The investigators will compare learning within children (taught words v. control words that are not explicitly taught) to make sure the learning that is happening is due to the treatment and not just maturation. The investigators will compare across groups to see if the group treated with More Familiar Sounding words learns more than the group treated with Less Familiar Sounding words.

Official Title
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Identification of Treatment Parameters That Maximize Language Treatment Efficacy for Children

Conditions
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Language Development Disorders

Intervention / Treatment
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* Behavioral: VAULT Phase 4


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Native English Speaking Pass pure tone hearing screening or medical report of normal hearing 2-3 Years of age at start of study MCDI expressive scales <10th percentile Exclusion Criteria: Parental reports of other diagnoses Enrolled in concurrent treatment elsewhere Nonverbal IQ <75 as measured by the Bayley scales Parents unable to consistently bring child to treatment sessions

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 4 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: The investigators will use treatment effect sizes to compare children to themselves (treatment v. control) and across groups (More Familiar Sounds v. Less Familiar Sounds).
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: More Familiar Sounds<br>Children in this condition will learn new words whose sounds are more like the sounds in the words the child already understands. | Behavioral: VAULT Phase 4<br>* Children will receive an input-based word learning treatment that is designed based on principles of statistical learning.<br>|
| Active Comparator: Less Familiar Sounds<br>Children in this condition will learn new words whose sounds are less like the sounds in the words the child already understands. | Behavioral: VAULT Phase 4<br>* Children will receive an input-based word learning treatment that is designed based on principles of statistical learning.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Treatment Effect Size | The investigators will count the number of spontaneous and probed productions of target and control words and calculate a treatment effect size (d). | Change from baseline through treatment, which will average an 8-week time frame. | 
| Number/Rate of Words Learned | The investigators will measure the number of words learned and the rate of words learned as reported by the parent on the MCDI starting prior to treatment and measured during, immediately following, and 4-6 weeks after the treatment. | Change from Initial Evaluation through Follow-up, which will average a 6-month time frame. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post Treatment Retention | The investigators will use probe data and parental report to determine how many of the words the child retained from treatment. | Change from end of treatment to follow up, which will average 4-6 weeks. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Late Talkers