A Rasch-Validation Study of a Novel Speaking Span Task

要旨

<jats:p>Working Memory refers to the capacity to temporarily retain a limited amount of information that is available for manipulation by higher-order cognitive processes. Several assessment instruments, such as the speaking span task, have been associated with the measurement of working memory span. However, despite the widespread use of the speaking span task, no study, to the best of my knowledge, has attempted to validate it using Rasch Measurement Theory. Rasch analysis can potentially shed light on the dimensionality of a complex construct such as working memory as well as examine whether a collection of items is working together to construct a coherent and reliable measure of a targeted population. This pilot study reports a Rasch analysis of a novel speaking span task, which was administered individually to 31 Japanese junior high school students and scored using a newly developed scoring system. Two separate analyses were conducted on the task: an analysis of the individual items using the Rasch dichotomous model and an analysis of the super items (sets) using the partial credit model. The results indicate that the task measures a coherent unidimensional latent variable and is thus a useful tool for measuring the construct. Moreover, Rasch analysis was shown to be suitable method for evaluating working memory tests.</jats:p>