Construct validity: are you measuring what you think you're measuring?Ī valid assessment should have good coverage of the criteria (concepts, skills and knowledge) relevant to the purpose of the examination.Criterion-related validity - how well does the test measure what you want it to?.Content validity - does the assessment content cover what you want to assess?.Face validity - do the assessment items appear to be appropriate?.There are several different types of validity: For example, a test of reading comprehension should not require mathematical ability. The validity of an assessment tool is the extent to which it measures what it was designed to measure, without contamination from other characteristics. ValidityĮducational assessment should always have a clear purpose, making validity the most important attribute of a good test. It is essential to read the manual thoroughly before conducting the assessment.

A coefficient of 0.9 or more indicates a high degree of reliability.Īssessment tool manuals contain comprehensive administration guidelines. How to be sure that a formal assessment tool is reliableĬheck in the user manual for evidence of the reliability coefficient.

The readiness of students for the assessment – for example, a hot afternoon or straight after physical activity might not be the best time for students to be assessed.The design of the marking schedule and moderation of marking procedures.The consistency in test administration – for example, the length of time given for the assessment, instructions given to students before the test.The phrasing and terminology of the questions.The suitability of the questions or tasks for the students being assessed.The length of the assessment – a longer assessment generally produces more reliable results.There is always some random variation that may affect the assessment, so you should always be prepared to question results.

No results, however, can be completely reliable. This puts you in a better position to make generalised statements about a student’s level of achievement, especially when you are using the results of an assessment to make decisions about teaching and learning, or reporting back to students and their parents or caregivers. Reliable assessment results will give you conﬁdence that repeated or equivalent assessments will provide consistent results. The validity of an assessment tool is the extent by which it measures what it was designed to measure. The reliability of an assessment tool is the extent to which it consistently and accurately measures learning.

Reliability and validity definition