Purpose: Children who experience early language delays include children with production delays only, children with both production and comprehension delays, and children who have global cognitive and other disabilities that affect their language development. Considerable research has focused on young children with only delays in productive language and on children older than 4 years with specific language impairment. Relatively less is known about children with co-occurring production and comprehension language delays under age 4 who do not have cognitive disabilities. These children are at relatively greater risk for persistent delays than young children with expressive delays only.

This efficacy trial is designed to examine the effects of therapist-plus parent implemented Enhanced Milieu Teaching (EMT) on young children 24–36 months of age with significant delays in expressive and receptive language. EMT is a conversation-based model of early language intervention that uses child interest and initiation as opportunities to model and prompt language use in everyday contexts. EMT is a well-established intervention for facilitating language and communication skills in young children with cognitive impairment; however, the effects of EMT on language-delayed children who do not have significant global cognitive impairments have not been examined in an efficacy trial. The study will test whether EMT can be effective in remediating language delays and preventing the development of secondary impairments.

Project Activities: This efficacy trial will compare EMT implemented by parents and therapists at home to a community "business as usual" comparison condition. Sixty children will be recruited and randomly assigned to each of two experimental conditions (EMT and Comparison) and will be followed longitudinally over 18 months. All children will be pretested, and results will be used to set language-learning targets. Children in the treatment group and their parents will work with therapists in 24 one-hour sessions. Children will be assessed at four time points (before and after the intervention, at 6 months and 12 months post-intervention), leading to a description and comparison of individual language growth trajectories over a period of 18 months.

Products: Researchers will provide evidence on whether: parent-plus-therapist implemented EMT improves language development, as well as children's behavior and social skills, over time; certain child characteristics measured at pre-treatment moderate language development for children; a relationship exists between parent support for language development and subsequent children's language development; there are corollary effects of participation in parent-plus-therapist-implemented EMT on parents and, if so, what the nature of the effects are; and, if fidelity standards developed in previous studies can be achieved for parent and therapist implementation of EMT in this study. Researchers will also provide a review of the costs of EMT when compared to business as usual in the community.

Structured Abstract

Setting: The study will take place in Tennessee.

Population: One hundred twenty children ages 24 –36 months who exhibit significant co-occurring delays in productive and receptive language skills (below 10th percentile for age group) will be included in the study.

Intervention: Experimental applications of EMT typically have included four sequential steps: (a) arranging the environment to increase the likelihood that the child will initiate interaction with the adult; (b) selecting specific language targets appropriate to the child's skill level (e.g., using –s with plural nouns); (c) responding to the child's initiations with prompts for elaborated language consistent with the child's targeted skills; and (d) functionally reinforcing the child's communicative attempts by providing access to requested objects, continued adult interaction, and feedback in the form of expansions and confirmations of the child's utterances.

Parents are taught to use EMT at home during 24 individual training sessions led by an experienced therapist. Standardized written and verbal information, modeling through therapist demonstration, role playing, video examples, viewing video of previous sessions, therapist feedback and support, and evaluation of child progress are used to teach parents the EMT procedures.

Research Design and Methods: The design involves random assignment to either EMT or a control "business as usual" condition. The key question in this efficacy study is whether the intervention works when implemented as designed. Thus, researchers will take steps to ensure and measure the fidelity of the EMT implementation and amount of language intervention treatments received by participants in both the experimental and control conditions. Children will be assessed four times over an 18-month period.

Control Condition: The control group will receive the community "business as usual" condition. This will include children who receive language intervention and those that do not, children enrolled in childcare and children cared for by their parents. These conditions represent the natural variability in treatment for this population and researchers will carefully document this variation.

Key Measures: Six types of measures will be used: (a) screening measures to determine participant inclusion; (b) baseline status measures of child and family; (c) standardized tests and other assessments of children's language assessed over time; (d) measures of child behavior and social skills over time reported by parents and teachers; (e) observational measures of parent-child interactions, including, direct measures of parent's implementation of EMT and measures of the child's language learning environment at home; and (f) measures of parent stress, competence related to parenting, and support for language.

Data Analytic Strategy: Researchers will test the efficacy of the intervention over time using individual growth curve models. These models will be used to test intervention effects by detecting differences between treatment and control groups in linear slopes (rates of change) over the four waves of measurement from pretest to the 18-month follow-up. Researchers will also examine how parent and child characteristics moderate the efficacy of the EMT language intervention, which may be important for understanding the conditions (presence of key child and parent characteristics) for which the EMT intervention protocol improves language and social and behavioral outcomes.

Products and Publications

Book chapter

Kaiser, A.P. (2014). Using Single Case Designs in Comprehensive Programs of Research. In T. Kratochwill, and J. Levin (Eds.), Single–Case Intervention Research: Methodological and Statistical Advances (pp. 309–323). Washington, DC: American Psychological Association.

Journal article, monograph, or newsletter

Kaiser, A.P., and Roberts, M.Y. (2013). Parents as Communication Partners: An Evidence Based Strategy for Improving Parent Support for Language and Communication in Everyday Settings. Perspectives on Language Learning and Education, 20(3): 96–111. doi:10.1044/lle20.3.96

R?oberts, M.R., Kaiser, A.P. Wolfe, C., Bryant, J., and Spidalieri, A. (2014). Effects of the Teach-Model-Coach-Review Instructional Approach on Caregiver use of Language Support Strategies and Children's Expressive Language Skills. Journal of Speech, Language, and Hearing Research, 57(5): 1851–1869. doi:10.1044/2014_JSLHR-L-13–011

Roberts, M., and Kaiser, A. (2012). Assessing the Effects of a Parent-Implemented Language Intervention for Children With Language Impairments Using Empirical Benchmarks: A Pilot Study. Journal of Speech, Language, and Hearing Research, 55: 1655–1670 . doi:10.1044/1092–4388(2012/11–0236)

Roberts, M.Y., and Kaiser, A.P. (2011). The Effectiveness of Parent-implemented Language Interventions: A Meta-analysis. American Journal of Speech-Language Pathology, 20(3): 180–199. doi:10.1044/1058–0360(2011/10–0055