Responses made by late talkers and typically developing toddlers during speech assessments

Purpose: Assessing toddlers’ speech is challenging. We explored responses made by late talkers and their typically developing peers in structured speech sampling contexts and determined if late talker subgroups could be identified. Method: Twenty-six late talkers and 26 age-matched typically developing toddlers participated in an expressive phonology assessment and an elicited non-word imitation test. We quantified the breadth of toddler responses used in a subset of monosyllabic stimuli from the toddler phonology assessment and in the non-word imitation test. Correlational and cluster analyses were conducted. Result: There were six response types: no response, protoword response, different verbal response, correct phoneme, common and uncommon phonological errors. Toddlers’ use of most of the response types correlated across the two sampling contexts. Use of the response types also correlated with several direct and parent-report assessments. There were significant group differences in the use of several response types in both sampling contexts. Five late talker subgroups were identified that presented with differing profiles of responses. Conclusion: Toddlers respond in a variety of ways during structured speech sampling contexts. Responses made by late talkers offer insights about the nature of late talking and their heterogeneity. Implications for research and clinical management of late talkers are discussed