Design and Analysis in Task-Based Language Assessment

Task-based language assessment (TBLA) grows from the observation that mastering the grammar and lexicon of a language is not sufficient for using a language to achieve ends in social situations. In TBLA, language use is observed in settings that are more realistic and complex than in discrete skills assessments and that typically require the integration of topical, social, and/or pragmatic knowledge along with knowledge of the formal elements of language. But designing an assessment is not accomplished simply by determining the settings in which performance will be observed. TBLA raises questions of just how to design complex tasks, evaluate students’ performances, and draw valid conclusions therefrom. This paper examines these challenges from the perspective of “evidence-centered assessment design.” The main building blocks are student, evidence, and task models, with tasks to be administered in accordance with an assembly model. We describe these models, show how they are linked and assembled to frame an assessment argument, and illustrate points with examples from task-based language assessment.