Disfluencies in non-stuttering adults across sample lengths and topics

Data on disfluencies in the speech of non-stuttering adults are relevant to several aspects of the assessment and treatment of adults who stutter. Currently, very few sources provide relevant data. In the existing literature on normally fluent speakers, there is no consistency in sample length or topic or in which types of disfluency are counted. Many studies report incomplete data, making it difficult to compare new results to previous ones. The purpose of this study was to assess the effect of sample length and topic on fluency levels in the speech of non-stuttering adult men. Monologues produced by 25 English-speaking men with no reported communication disorder were analyzed for the presence of disfluencies. The group means for total disfluencies were between 6 and 8 per 100 syllables for all samples. A within-subjects Length (3) by Topic (3) ANOVA found a significant interaction (Length by Topic), however, the clinical importance of this result is minimal. The mean number of within-word disfluencies (also called stuttering-like disfluencies or SLDs) was below 1.5 per 100 syllables for all samples, although there was some variation across individual speakers. The data presented will be useful to clinicians and to researchers interested in disfluencies in spontaneous speech.Learning outcomes: Readers will be able to (1) identify several methodological problems in studies of disfluency including counting methods and descriptions of participants; (2) identify the range of within-word disfluencies (also called SLDs) and other disfluencies in this study and other similar ones; (3) know whether topic/type of speech or sample length is more likely to affect disfluency levels in non-stuttering adults.