Primary objective: To compare the everyday communication of individuals with mild and moderate dysarthria and concomitant cognitive-communication impairments following traumatic brain injury (TBI).
Methods and procedures: Five participants with mild dysarthria and five with moderate dysarthria following TBI were recorded during telephone service enquiries with bus timetable call centre operators. Transcripts were analysed using exchange structure analysis derived from systemic functional linguistics. Listener comfort ratings were collected using a novel equal appearing interval scale to measure how comfortable people would feel interacting with the participants.
Main outcomes and results: Participants with moderate dysarthria were not necessarily penalized for having poorer intelligibility during bus timetable service encounters. While participants with moderate dysarthria were given poorer listener comfort ratings, this did not affect the way information was exchanged with bus timetable call centre operators. These findings were attributed to the powerful interactional role of TBI participants as customers, the amount of disability awareness training and experience held by call centre operators and the highly structured nature of bus timetable service enquiries. Listener comfort ratings could be predicted with moderate accuracy from intelligibility scores.
Conclusions: Service encounters where individuals with TBI are placed in a powerful interactional role of customer may be functional generalization tasks for people with moderate dysartrhia. Training and education of service providers may also impact on the communicative effectiveness of individuals with TBI.