Disfluency characteristics of 2-, 4-, and 6- yr-old males

Fluency characteristics of 36 nonstuttering males aged 2, 4, and 6 yr are presented in terms of patterns of disfluency and relationships among disfluency variables. The most frequently occuring disfluency types at each age level were revision-incomplete phrase and interjections; the least noted type was part-word repetitions for 2- and 4-yr olds and disrhythmic phonations for 6-yr-olds. Patterns of disfluency appear to be similar at all age levels studied, except that the 2-yr-old pattern showed greater magnitudes in various disfluency types. A range exists in the relationships among individual disfluency types, from moderately strong relationships between, for example, revision-incomplete phrase and interjections to lack of linear relationships between, for example, interjections and phrase repetitions. A linguistic factor may be strong within certain disfluency types. e.g., revision-incomplete phrase, interjections, and word repetitions, whereas a motor factor may be operative in others, e.g., part-word repetitions and disrhythmic phonations.