waysdaa.blogg.se - Assessing reliability psychology

For example, if some participants are taking the test in a hurry in a public and noisy place and others are taking it at leisure in their office, this could impact reliability.

Have a consistent environment for participants. For test results to be consistent, it’s important that the test environment is consistent – try to ensure that all participants have the same amount of time to take the test in and have a similar environment.

You can also get guidance from an earlier post on this blog, How many questions do I need on my assessment? In their excellent book, Criterion-Referenced Test Development, Shrock and Coscarelli suggest a rule of thumb is 4-6 questions per objective, with more for critical objectives.

Use enough questions to assess competence. Although you need a sensible balance to avoid tests being too long, reliability increases with test length.

Here are six practical tips to help increase the reliability of your assessment: How can you increase the reliability of your assessments? To learn more about validity, see my earlier post Six tips to increase content validity in competence tests and exams. Continuing the kitchen scale metaphor, a scale might consistently show the wrong weight in such a case, the scale is reliable but not valid.

Just like a kitchen scale that doesn’t work, an unreliable assessment does not measure anything consistently and cannot be used for any trustable measure of competency.Īs well as reliability, it’s also important that an assessment is valid, i.e. But if the scale is not working properly and is not reliable, it could give you a different weight each time. If the scale is reliable, then when you put a bag of flour on the scale today and the same bag of flour on tomorrow, then it will show the same weight.

A test with poor reliability might result in very different scores across the two instances. If you were to deliver an assessment with high reliability to the same participant on two occasions, you would be very likely to reach the same conclusions about the participant’s knowledge or skills. This blog post explains what reliability is, why it matters and gives a few tips on how to increase it when using competence tests and exams within regulatory compliance and other work settingsĪn assessment is reliable if it measures the same thing consistently and reproducibly. Reliability (how consistent an assessment is in measuring something) is a vital criterion on which to judge a test, exam or quiz.