Measurement provides us with powerful tools that we can use to improve our tests from the perspective of both students and teachers. This article offers tips for using these measurement tools for both items and tests.
Item analysis refers to methods used to review and improve the items in our tests.
Test review refers to techniques we can use to examine the stability and appropriateness of each test as a whole.
4 Tips for Item Analysis
1. Know the item difficulty
Item difficulty can help you set the appropriate expectations when measuring student knowledge. This can help you check the appropriateness of items and associated skills for your class or grade level and identify gaps in instruction.
2. Look for problematic items
The item discrimination can tell you if items are confusing or possibly even miskeyed. Look out for correct answers with negative discriminations as they are problematic and should be revised before further use or just removed from the test.
3. Make sure the distractors are plausible
Look at the distractors (incorrect choices) for each item to see if students are selecting each choice at a similar rate. If some distractors are not being chosen then they are not a reasonable option and should be reviewed.
4. Integrate feedback from instruction
The item analysis is enhanced if feedback from teachers and students is used to support an item review. Teacher and student feedback can identify items that are inappropriate for the current skill level and whether the test is balanced in length.
4 Tips for Test Review
1. Build assessment confidence using reliability
Obtain the test’s reliability coefficient. This tells you how consistent your test scores are and can provide the teacher with confidence that the test they are using is of the highest quality.
2. Seek to improve reliability
Cronbach’s alpha reliability can be improved using Tips 1–3 discussed in the previous section. Consider an item analysis and find ways to improve the test for the next testing session.
3. Check the test’s validity
What evidence supports your interpretations of the test scores? A review of the literature or verification that your items are linked to the right skills and standards can inform you how much validity your test has.
4. Support your test plan using validity
The body of evidence behind your test can provide evidence that your test plan and content is appropriate for the students you are measuring. Consider making revisions to the test plan if the test review reveals that the test content is not appropriate.
These tips provide a solid foundation to improve the quality of your assessment at both the item and test level. Test improvement is an ongoing process that requires feedback from the item development and exam form creation stages of the assessment development cycle.
Understanding Key Psychometric Terms
Review the terms below for a quick reference covering some common psychometric terms, including interpretative guidelines.
.10 to .19: Low
.20 to .29: Good
.30+: Very Good
(Indicates whether items are measuring the same general skill)
.80 to .89: Good