How to examine construct validity of item banks

Abstract

In this study data is brought to support an approach for assuring the content validity of item banks and for examining their construct validity. The method is an application of Guttman's concept of using mapping sentences for theory construction in the domain of “simple fraction’. The construct validity of the theory used for the creation of the item bank was tested by selecting two samples of items which are referenced in the same structuple (criterion). The Yule weak monotonicity coefficients of the items' connections were calculated and represented in two different matrices and in two different space diagrams. The results show clearly a similarity in both the structure of the space diagrams of any two parallel samples and in the partition of the points into regions, i.e., regions according to the classification of the items represented by them on the basis of the facets defined by the mapping sentences. Consequently, it may be concluded that the results support the construct validity of the theory on the basis of which the bank has been created.