Normative disfluency data for early childhood stuttering.

Although the past 50 years of research on early childhood stuttering and normal disfluency have produced vital information on the general features of disfluent speech behavior of young children, an adequate normative reference for early stuttering does not exist. The purpose of this report is to provide such reference and to provide a basis for clinical needs of differential diagnosis of stuttering from normal disfluency. Data are presented from 90 stuttering children ages 2 to 5 within 6 months of stuttering onset and from 54 age-matched normally fluent children. Means for disfluency types are presented. No significant differences were found for gender or for age. Stuttering-like disfluencies (SLD) did differ significantly for the stuttering and fluent groups, but other disfluencies (OD) did not. A weighted SLD is defined to further clarify differences between the groups. The pattern of disfluency types for normally fluent and for mild, moderate, and severe stuttering is presented. Stuttering is shown to be qualitatively as well as quantitatively different from normal disfluency even at the earliest stages of stuttering. Clinical and research implications are discussed.