After a test item is written but before it is included in an actual test, the item is put through field testing. Field testing is quality control for test items. Field testing can identify items that contain mistakes or are confusing.
In a field test, test items are given to students, but the scores for those items are not applied toward students’ test scores to prevent problematic items from negatively and unfairly affecting student grades.
Field testing provides valuable information about test items, such as how difficult each item is, how many students select each specific answer choice, and which items might be biased in favor of or against certain groups. There are two main ways to field test items.
Embedded Field Testing
In an embedded field test, the items are given in an actual test. Students are told that some of the items in their test will not count but are not told which items those are, so students try their best on all items. When field-tested items are embedded in the test, researchers can collect information about how students will do on these items. Embedding field-test items to tests will either add additional items, which makes the tests longer, or replace actual test items to make room for the field-test items, which reduces the amount of information received from the actual test.
Embedded field tests are often used in testing programs with large numbers of test takers, in testing programs where the content does not change a lot, or in testing programs where access to test takers is limited. Currently, the Kansas Assessment Program uses an embedded field test for new items.
Explicit Field Testing
In an explicit (or stand-alone) field test, the field test may be given on a different day from the real test. Students taking this test know that all of the items in the test do not count. Because students know this, they sometimes will not do their best on these items, and the data collected can be misleading. Because explicit field tests generally look like the final test, though, researchers get good information about individual items and items as a collection. Explicit field tests are often used at the beginning of an assessment program when new content or new test items are being introduced or when the test group is very small.