Many language teachers harbour a deep mistrust of tests and of testers. The starting point for this book is the admission that this mistrust is frequently well-founded. It cannot be denied that a great deal of language testing is of very poor quality. Too often language tests have a harmful effect on teaching and learning, and fail to measure accurately whatever it is they are intended to measure.

Backwash

The effect of testing on teaching and learning is known as backwash, and can be harmful or beneficial. If a test is regarded as important, if the stakes are high, preparation for it can come to dominate all teaching and learning activities. And if the test content and testing techniques are at variance with the objectives of the course, there is likely to be harmful backwash. An instance of this would be where students are following an English course that is meant to train them in the language skills (including writing) necessary for university study in an English-speaking country, but where the language test that they have to take in order to be admitted to a university does not test those skills directly. If the skill of writing, for example, is tested only by multiple choice items, then there is great pressure to practise such items rather than practise the skill of writing itself. This is clearly undesirable.

We have just looked at a case of harmful backwash. However, backwash can be positively beneficial.