Mother and child speech rates as a variable in stuttering and disfluency.

Three questions were addressed in this study: (a) Do mothers of stuttering children talk faster than mothers of nonstuttering children, (b) do stuttering children talk faster than nonstuttering children, and (c) is there a relationship between child's rate of speech and mother's rate of speech in dyadic conversation? Twelve nonstuttering preschool boys and their mothers were matched with 12 stutterers and their mothers. Ten min of free-play interaction between alternated mother-child dyads were video recorded. Speech rates, defined as syllables per second in fluent utterances, were calculated. Results demonstrated that mothers of stutterers talked significantly faster to all children. Stutterers spoke slower than nonstutterers, and severe stutterers spoke slower than moderate stutterers. A correlational analysis revealed that the more the child stuttered, the slower he talked during fluent speech. Further, the slower the child talked during fluent speech, the faster the mother interacting with him talked. The results reveal an interactive and complex relationship between mother and child speech rates. The interpretation of results relating to child speech rates was complicated by post hoc analyses revealing a significant relationship between speech rates and utterance length.