The Washback Effects of Task-based Assessment on the Iranian EFL Learners' Grammar Development

There is some evidence to suggest that tests have washback effects on teaching and learning processes (Alderson & Wall, 1993). Task-based language assessment (TBLA) as an alternative mode of language testing is believed to be of washback effect on language learning (Mislevy, Almond & Steinberg, 2002). However, the nature of this effect on the development of different language elements and skills is yet to be explored. In a partial attempt to address the lacuna, this study investigates the washback effect of TBLA on English as a foreign language learners' (EFL) grammar development. Seventy-four EFL learners were randomly selected from 110 pre-intermediate learners of a language institute and were divided into two groups of control and experiment. To ensure the same level of grammar ability, both groups took a grammar pre-test at the outset of the project. During ten sessions of treatment, the groups received the same kind of grammar instruction, however, the experimental group took a researcher made task-based grammar quiz every three sessions, but the control group took traditional grammar quizzes. After the treatment, the two groups took a grammar post-test. The analyses revealed a positive washback effect of the TBLA on the grammar development of EFL learners. The findings imply that TBLA as a pedagogical measurement tool can well replace the classic assessment procedures as all educational efforts including testing and assessment procedures are planned to maximize the educational gains and developments. (C) 2014 The Authors. Published by Elsevier Ltd.