Folia Phoniatr Logop 2007;59:306–317

Effects of Speech Stimuli and Dysarthria Severity on Intelligibility Scores and Listener Confidence Ratings for Speakers with Cerebral Palsy

Hustad K.C.
Department of Communicative Disorders and Waisman Center, University of Wisconsin, Madison, Wisc., USA
email Corresponding Author

 goto top of outline Key Words

  • Speech intelligibility
  • Cerebral palsy
  • Dysarthria

 goto top of outline Abstract

This study examined differences among transcription intelligibility scores and listener confidence ratings for three different types of speech stimuli – single words, unrelated sentences, and sentences forming a narrative – all produced by speakers with dysarthria. Twelve speakers with dysarthria of varying severity secondary to cerebral palsy and 144 listeners participated in this study. Results showed that both intelligibility scores and confidence ratings were differentially affected by both stimuli and severity. For speakers with mild, moderate, and severe dysarthria, intelligibility scores were higher for narratives than for either of the other two types of speech stimuli. For speakers with mild dysarthria, sentences were substantially more intelligible than single words. However, for speakers with moderate, severe, and profound dysarthria, the difference in intelligibility scores for sentences and single words was small or nonsignificant. Confidence ratings did not follow the same pattern as intelligibility data, suggesting a mismatch between listeners’ perception of their performance and their actual performance on intelligibility tasks.

Copyright © 2007 S. Karger AG, Basel

 goto top of outline References
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 goto top of outline Author Contacts

Katherine Hustad
475 Waisman Center
1500 Highland Avenue
Madison, WI 53705 (USA)
Tel. +1 608 265 9977, Fax +1 608 263 7710, E-Mail

 goto top of outline Article Information

Portions of these data were presented at the American Speech- Language and Hearing Association Annual Convention, Chicago, Ill. (November, 2003).

Number of Print Pages : 12
Number of Figures : 6, Number of Tables : 5, Number of References : 18

 goto top of outline Publication Details

Folia Phoniatrica et Logopaedica (International Journal of Phoniatrics, Speech Therapy and Communication Pathology)

Vol. 59, No. 6, Year 2007 (Cover Date: October 2007)

Journal Editor: Schutte, H.K. (Groningen)
ISSN: 1021–7762 (print), 1421–9972 (Online)

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