Applying main concept analysis (MCA) to assess picture description in Cantonese AphasiaBank of unimpaired speakers and those with aphasia

Abstract

The present study applied Main Concept Analysis (MCA) to four new picture description tasks in unimpaired speakers and speakers with aphasia in Cantonese. Discourse language samples of 150 normal speakers and 62 speakers with aphasia, among which 31 were fluent aphasia and 31 were non-fluent aphasia, were extracted from the Cantonese AphasiaBank. Main Concept checklists were established with normative scores stratified by age, gender and education level for each task, namely ‘Broken window’, ‘Refuse umbrella’, ‘Cat rescue’ and ‘Flood’. Results indicated that among the unimpaired speakers, young and middle age group produced more accurate and complete picture descriptions with higher efficiency than old group. Furthermore, high education group produced more accurate and complete content than low education group but the groups did not differ in efficiency. Application to PWA revealed that fluent aphasia participants produced more accurate and complete descriptions with higher efficiency than non-fluent aphasia speakers. MCA performance of PWA could also be predicted by their fluency type and object naming test score. Effects of different picture description tasks on MCA performance were discussed. All in all, the MCA checklist developed was a clinically-friendly norm-referenced discourse assessment tool that could efficiently and consistently offer diagnostic insights on the clients’ functional communication success and evaluate treatment efficacy.