This study aimed to evaluate the item model fit by equating the forms of the PISA 2018 mathematics subtest with concurrent common items equating in samples from Türkiye, the UK, and Italy. The answers given in mathematics subtest Forms 2, 8, and 12 were used in this context. Analyzes were performed using the Dichotomous Rasch Model in the WINSTEPS…

Testlets have advantages such as making it possible to measure higher-order thinking skills and saving time, which are accepted in the literature. For this reason, they have often been preferred in many implementations from in-class assessments to large-scale assessments. Because of increased usage of testlets, the following questions are…

Changing the order of items between alternate test forms to prevent copying and to enhance test security is a common practice in achievement testing. However, these changes in item order may affect item and test characteristics. Several procedures have been proposed for studying these item-order effects. The present study explores the use of…