Assessing Vocal Development in Infants and Toddlers Who Are Hard of Hearing: A Parent-Report Tool.

The main purpose of the current investigation was to determine whether the Vocal Development Landmarks Interview-Experimental Version (VDLI-E) was sensitive to variation in the vocal development of infants and toddlers who are hard of hearing. The VDLI-E is an interactive parent interview that uses audio samples of authentic infant vocalizations to make targeted vocal behaviors clear and understandable to parents without the need for technical terms, verbal descriptions, or adult modeling of infant productions. The VDLI-E was found to be sensitive to age and hearing and was related to performance on concurrent measures of early auditory skills, expressive vocabulary, and overall expressive language abilities. These findings provide preliminary support for the utility of this measure in monitoring the impact of early auditory experiences on vocal development for 6- to 18-month-old children who are hard of hearing.