Validity: the assessment must cover allaspects, and only those aspects, of pupils’achievement relevant to a particular purpose.
Reliability: it should be designed so that users can have confidence that the results are sufficiently accurate and consistent for their purpose.
Impact: it should not only measure performance but have desirable consequences for teaching, learning and pupils’ motivation for learning. Assessment generally has a strong impact on the curriculum and on pedagogy, so it is vital that any adverse effects are minimised.
Practicability: the resources required to provide it teachers’ time, expertise and cost, and pupils’ learning time – should be commensurate with the value of the information for its users.