Validity and washback in language testing

Washback, a concept prominent in applied linguistics, refers to the extent to which the introduction and use of a test influences language teachers and learners to do things they would not otherwise do that promote or inhibit language learning. Some proponents have even maintained that a test's validity should be appraised by the degree to which it manifests positive or negative washback, a notion akin to the proposal of 'systemic validity' in the educational measurement literature. This article examines the concept of washback as an instance of the consequential aspect of construct validity, linking positive washback to so-called authentic and direct assessments and, more basically, to the need to minimize construct under- representation and construct-irrelevant difficulty in the test.