Reliability of main event measurement in the discourse of individuals with aphasia

Abstract

Background: Quantitative measures of discourse skills of adults with aphasia can be valuable in documenting evidenced‐based practice. Comprehensive assessment of narrative discourse should include a measure of the ability to relay main events (Nicholas & Brookshire, 1995 Nicholas, L. E. and Brookshire, R. H. 1995. Presence, completeness, and accuracy of main concepts in the connected speech of non‐brain‐damaged adults and adults with aphasia.. Journal of Speech and Hearing Research, 38(1): 145–156. [Crossref], [PubMed] , [Google Scholar]; Wright, Capilouto, Wagovich, Cranfill, & Davis, 2005 Wright, H. H., Capilouto, G. J., Wagovich, S. A., Cranfill, T. and Davis, J. 2005. Development and reliability of a quantitative measure of adults' narratives.. Aphasiology, 19(3/4/5): 263–273. [Taylor & Francis Online] , [Google Scholar]). Wright et al. (2005 Wright, H. H., Capilouto, G. J., Wagovich, S. A., Cranfill, T. and Davis, J. 2005. Development and reliability of a quantitative measure of adults' narratives.. Aphasiology, 19(3/4/5): 263–273. [Taylor & Francis Online] , [Google Scholar]) compared the ability of younger and older healthy adults to relate main events in response to pictured stimuli. Results indicated that the younger group produced a significantly higher proportion of main events as compared to the older group and that the main events measure was stable for individual participants over time. However, performance data and data supporting the stability of the main events measure for individuals with aphasia are needed to extend the clinical usefulness of the main events measure as an assessment tool. Aims: The purpose of this study was (a) to compare the performance of healthy adults and adults with aphasia on their ability to convey main events in pictured stimuli and (b) to establish session‐to‐session reliability of the authors' main events measure. Methods & Procedures: Eight adults with aphasia (APH) and eight neurologically intact adults (NI) participated in the study. Participants attended two sessions, 7–21 days apart. Each time, participants gave an account of the events from two pictures and two picture sequences (Nicholas & Brookshire, 1993 Nicholas, L. E. and Brookshire, R. H. 1993. A system for quantifying the informativeness and efficiency of the connected speech of adults with aphasia.. Journal of Speech and Hearing Research, 36(2): 338–350. [Crossref], [PubMed] , [Google Scholar]). The resulting language samples were analysed for the proportion of main events conveyed, and test–retest reliability of the measure was assessed. Outcomes & Results: NI adults told a significantly higher proportion of main events than adults with aphasia. The main effect for picture stimulus was also significant; participants told significantly more main events in response to sequential versus single picture stimuli, regardless of group. Test–retest results yielded strong, positive correlations between sessions for both groups. Conclusions: Results indicate that adults with and without aphasia differ in their ability to express the relations and causal links among units of information. Results also indicate that Wright and colleagues' (2005 Wright, H. H., Capilouto, G. J., Wagovich, S. A., Cranfill, T. and Davis, J. 2005. Development and reliability of a quantitative measure of adults' narratives.. Aphasiology, 19(3/4/5): 263–273. [Taylor & Francis Online] , [Google Scholar]) main events measure demonstrates sufficient stability to provide the foundation for its potential use as a pre‐ and post‐treatment measure. Finally, the finding that the proportion of main events provided in response to stimuli varied according to the nature of the stimuli is consistent with the findings of Wright et al. (2005 Wright, H. H., Capilouto, G. J., Wagovich, S. A., Cranfill, T. and Davis, J. 2005. Development and reliability of a quantitative measure of adults' narratives.. Aphasiology, 19(3/4/5): 263–273. [Taylor & Francis Online] , [Google Scholar]) and suggests that even for individuals with aphasia, relationships between elements depicted in pictures may be more easily identified and conveyed when sequential pictures are provided as stimuli.