There are lots of ways in which classroom assessment practices can be improved in order to increase reliability, and one of the most immediate is to improve so-called inter-rater reliability and intra-rater reliability.

the conditions in which students take the assessment.

the subjectivity of the material to be assessed.the assessor’s unfamiliarity with robust assessment practices.the assessor’s unfamiliarity with the topic being assessed.Some (of the many) sources of error include:

Because it is a proxy for something unseen, and because interpretation is often part of making sense of the information derived from an assessment, error is always present in some form or other. the accuracy and consistency of the interpretations derived from assessment responses.ĭesigning questions and assessment processes which work in the same way for different students at different points in time is a skill to be honed, but one that can pay repeated dividends to teachers and their students.Īn assessment is a means by which we can create a set of circumstances in which a student can represent their knowledge, skill and understanding in an observable form.the precision of the questions and tasks used in prompting students’ responses.There are lots of factors which contribute to the reliability of an assessment, but two of the most critical for teachers to acknowledge are: As we saw with validity, a determination of how reliable an assessment needs to be is informed by its intended end uses. High-stakes decisions need highly reliable information. Reliability in the assessment of student learning is also about accuracy and consistency and, as a rule, the higher the stakes of the decision we want to make based on assessment information, the more accurate and consistent we want the information to be. So how much do you weigh? Which is the correct reading (if either of them is indeed ‘correct’)? Most people answer this question with the obvious response (‘the lower one’), but at the heart of the issue is the reliability of the measurement: its accuracy and consistency over time, and context. Have you ever weighed yourself in the morning, and then again in the afternoon? If you did, you probably got slightly different readings each time. In this blog, we turn our focus to reliability. In previous blogs we looked at fitness for purpose and validity of judgements and conclusions. This blog post on assessment reliability was first published as a guest post on The Association of School and College Leaders’ (ASCL) website.

Assessing reliability psychology