Adaptation and validation of the main concept analysis of spoken discourse by native Japanese adults

Many people with aphasia demonstrate problems of oral production at the discourse level. The Main Concept Analysis (MCA) for oral discourse production is a published evidence-based battery for quantifying the degree of presence, accuracy, completeness, and efficiency of targeted main concepts in oral discourse. In Japan, such a standardized tool specialized for assessing spoken discourse is currently lacking. The purpose of this study was to adapt the Japanese version of MCA for oral discourse production (the Japanese-MCA) and examine its validity and reliability. Stage 1 of the study involved the establishment of linguistically-specific main concepts (MCs) of the Japanese-MCA. Ten speech-language-hearing therapists and 60 healthy participants who were native monolingual Japanese speakers were recruited to determine MCs. Stage 2 examined the criterion validity and reliability of the Japanese-MCA. Language samples of 20 participants with aphasia, as verified by Standard Language Test of Aphasia (SLTA), and 20 healthy older participants were used. Results of Stage 1 of the study yielded normative data with a set of target MCs that were geographically and linguistically specific for use in Japan. The results also revealed the comparability of the Japanese-MCA and previously reported versions of other languages. Stage 2 findings indicated not only a high correlation of criterion validity, but also good reliability of the test. With established norms and specific scoring criteria of the Japanese-MCA, it is believed that this new tool will become a useful addition to clinical management and research of aphasia in Japan.