Progressive dysarthria and augmentative and alternative communication in conversation: establishing the reliability of the Dysarthria-in-Interaction Profile.

Background: The Dysarthria-in-Interaction Profile's potential contribution to the clinical assessment of dysarthria-in-conversation has been outlined in the literature, but its consistency of use across different users has yet to be reported.

Aims: To establish the level of consistency across raters on four different interaction categories. That is, how reliable clinicians are when rating a series of videos. A secondary aim was to investigate the relationship between raters' estimates of dysarthric speech intelligibility and their rating of each dyad's overall interaction.

Methods & Procedures: Ten UK speech and language therapists rated independently a series of 40 video samples featuring people with progressive dysarthria in conversation with family members. An equal number of video samples was selected from a collection of recordings featuring four different types of interactional relationship.

Outcomes & Results: The results show that practising speech and language therapists can rate consistently, and with a high degree of agreement, a series of everyday conversation videos featuring dyads with progressive dysarthria and presenting at different interaction levels. The results also indicate that speech intelligibility does not predict the level of impairment in the interaction in a systematic way suggesting that conversation contains elements that are not directly related to speech intelligibility.

Conclusions & Implications: Further work is required to establish the clinical functionality of this tool, but the results presented here support the development of this conversation profiling system, particularly for people experiencing significant intelligibility problems but remaining highly interactive/communicative.