Journal of Fluency Disorders 33 (2008) 120–134 The effect of SpeechEasy on stuttering frequency, speech rate, and speech naturalness Joy Armson ∗ , Michael Kiefte School of Human Communication Disorders, Dalhousie University, 5599 Fenwick Street, Halifax, Nova Scotia B3H 1R2, Canada Received 12 July 2007; received in revised form 15 April 2008; accepted 21 April 2008 Abstract The effects of SpeechEasy on stuttering frequency, stuttering severity self-ratings, speech rate, and speech naturalness for 31 adults who stutter were examined. Speech measures were compared for samples obtained with and without the device in place in a dispensing setting. Mean stuttering frequencies were reduced by 79% and 61% for the device compared to the control conditions on reading and monologue tasks, respectively. Mean severity self-ratings decreased by 3.5 points for oral reading and 2.7 for monologue on a 9-point scale. Despite dramatic reductions in stuttering frequency, mean global speech rates in the device condition increased by only 8% in the reading task and 15% for the monologue task, and were well below normal. Further, complete elimination of stuttering was not associated with normalized speech rates. Nevertheless, mean ratings of speech naturalness improved markedly in the device compared to the control condition and, at 3.3 and 3.2 for reading and monologue, respectively, were only slightly outside the normal range. These results show that SpeechEasy produced improved speech outcomes in an assessment setting. However, findings raise the issue of a possible contribution of slowed speech rate to the stuttering reduction effect, especially given participants’ instructions to speak chorally with the delayed signal as part of the active listening instructions of the device protocol. Study of device effects in situations of daily living over the long term is necessary to fully explore its treatment potential, especially with respect to long-term stability. Educational objectives: The reader will be able to discuss and evaluate: (1) issues pertinent to evaluating treatment benefits of fluency aids and (2) the effects of SpeechEasy on stuttering frequency, speech rate, and speech naturalness during testing in a dispensing setting for a relatively large sample of adults who stutter. © 2008 Elsevier Inc. All rights reserved. Keywords: Stuttering; Fluency aid; Stuttering treatment outcome; SpeechEasy A considerable amount of experimental evidence has shown that altered auditory feedback (AAF) can decrease stuttering in the laboratory (see review by Lincoln, Packman, & Onslow, 2006). The results of these laboratory studies, which delivered AAF via large equipment arrays, motivated development of a clinical application of AAF in the form of miniature, body-worn devices. One of the best known of these devices, marketed under the trademark of SpeechEasy, is now distributed widely throughout the world. ∗ Corresponding author. Tel.: +1 902 494 5154; fax: +1 902 494 5151. E-mail address: j.armson@dal.ca (J. Armson). 0094-730X/$ – see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.jfludis.2008.04.002