Analyzing caregiver linguistic input during a remote dialogic book-sharing interventions for toddlers with clefts. - PROJECT SUMMARY Cleft palate with or without cleft lip (CP±L) is among the most common congenital conditions, affecting approximately 1 in 450 infants worldwide and 1 in 1050 infants in the United States. While most children undergo early surgical repair, many continue to experience significant speech and language delays that impact social and academic development. Recent research has highlighted the potential of parent/caregiver-focused interventions in supporting language development in children with CP±L, but the specific mechanisms underlying these interventions are not yet fully understood. This goal of this study is to examine the mechanistic role of parent/caregiver's speech inputs in supporting language development in toddlers with CP±L. This study fills critical gaps by transcribing, coding, and analyzing observational data from a remote dialogic book-sharing (DBS) intervention for toddlers with CP±L (randomized controlled trial or RCT of the intervention, Book Sharing for Toddlers with Clefts – BOOST; NCT06338319). Unlike prior work relying on audio-only data, this research uniquely includes gestural communication, such as deictic gestures, which may act as compensatory strategies in children with impaired speech and are linked to vocabulary development. Through language sample analysis of video-recorded parent-child book-sharing interactions collected at five timepoints, we will examine how parent/caregiver language quantity (e.g., utterance frequency, speech rate, pause time) and responsiveness (e.g., contingent responses, conversational turns, deictic gestures, personalization, categorization, and temporal responses) change over the course of the intervention. We will also evaluate how these changes relate to expressive and receptive language improvements in children with CP±L. Clinically, this work will clarify caregiver-mediated mechanisms to enhance targeted interventions for children with CP±L and other language delays, improving long-term developmental outcomes. In line with the R15's dual goals, the project will build research infrastructure by training undergraduate and graduate students in developmental research methods, including transcription, coding, and data analysis. This training will provide hands-on interdisciplinary experience, strengthen research capacity at a primarily undergraduate institution, and foster a collaborative environment that integrates clinical and developmental science. By moving beyond traditional speech metrics to incorporate gesture and multidimensional responsiveness, this study advances understanding of parent input's role in language development for children with CP±L and lays a foundation for future research to refine and expand parent-mediated interventions. Chong R15
