Cognitive diagnostic models (CDMs) have received much interest within the field of language testing over the last decade due to their great potential to provide diagnostic feedback to all stakeholders and ultimately improve language teaching and learning. A large number of studies have demonstrated the application of CDMs on advanced large-scale…

The TOEFL iBT test was introduced in 2005 to better reflect the language demands of real-life academic tasks than did previous versions of the test. The task-based design of the test was intended to support the interpretation of its scores as a trustworthy measure of international students' ability to use English in an academic environment. Until…