BUFFER ITEM

n. an item which is currently of no particular relevance, yet serves a purpose. In an experiment, it is interspersed between other items to complete the test. Although it is not scored, it disguises items instead of separating them into those which are relevant (valid) and irrelevant (invalid).

BUFFER ITEM: “During experimentation, buffer items are introduced into the test to reduce predictability and increase validity.”
 

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