Correct Information Unit（CIU）による失語症談話検査の開発—信頼性と妥当性の検討

Development of an aphasia discourse evaluation using Correct Information Unit(CIU):Reliability and validity studies

　失語症のある人の談話の情報伝達量と情報伝達効率を評価する検査としてCorrect Information Unit（以下，CIU）による失語症談話検査試案を開発した．この検査は，失語症のある人の情景画説明時の談話を，自立語数，CIU数，％CIUで評価するものである．本研究は，その信頼性と妥当性を検証することを目的とする．対象は軽度〜中等度の失語症のある人で，信頼性の検証は8名，妥当性の検証は18名に実施した．その結果，自立語数とCIU数は検者内および検者間信頼性で高い信頼性を認めた．CIU数と％CIUは標準失語症検査補助テストのまんがの説明課題と本試案との成績間に有意な相関を認めた．さらに，CIU数と％CIUは中等度失語群よりも軽度失語群で有意に高値となった．これらの結果から，CIUによる失語症談話検査試案は，信頼性および妥当性ともに高い検査であり，臨床的有用性を持つことが示された．

　To evaluate the discourse of people with aphasia, we developed a preliminary aphasia discourse evaluation using Correct Information Units (CIUs) to measure informativeness and efficiency during discourse. This test evaluates the discourse of persons with aphasia as they describe a single picture in terms of the number of independent words, the CIU count, and the percentage of CIUs (% CIUs). This study aimed to verify the reliability and validity of the CIU. The participants all had mild to moderate aphasia. Eight participants were involved in reliability testing, and 18 participants were involved in validity testing. The results showed both high intra- and inter-rater reliability for the number of independent words and CIU count. Moreover, we observed that the CIU count and % CIUs correlated significantly with performance on the sequential picture description task of the Standard Language Test of Aphasia- Supplementary Test that is used to assess the discourse ability of people with aphasia. Both the CIU count and % CIUs were significantly higher in the mild aphasia group than in the moderate aphasia group. Based on these results, we conclude that this aphasia discourse evaluation using CIUs has high reliability, validity, and clinically utility.