ABA glossary
Preference assessment
Definition
A structured way to identify the items or activities a person prefers and rank them, so the most preferred ones can be tested and used as reinforcers.
In plain words
Asking a learner or caregiver "What does she like?" is a start, but people often guess wrong, and preferences change from day to day. A preference assessment lets the learner show what they choose. Common formats are paired-stimulus (two items at a time), multiple-stimulus with or without replacement (several items at once), free-operant (free access, timing engagement), and single-stimulus (one item at a time). The result is a ranking. High-ranked items are likely, but not guaranteed, to work as reinforcers.
Example from a session
Before teaching, the RBT runs a brief MSWO with bubbles, a puzzle, a music toy, a spinning top, and a ball, as the plan specifies. Rosa picks the music toy first, then bubbles, then the spinning top, then the ball, then the puzzle. The RBT records the order. As the plan directs, she uses the top item for the hardest targets and repeats the brief MSWO at the start of each session, because preferences shift.
For BCBA candidates and supervisors
Analysts choose a format by weighing time, the learner's skills (scanning an array, choosing between items), and the risk of problem behavior when items are removed; free-operant formats avoid removal and suit learners whose problem behavior is triggered by taking items away. Preference is not the same as reinforcer effectiveness, so high-stakes programs may follow up with a reinforcer assessment. Analysts also watch for position bias, satiation, and edible items dominating the ranking, and they reassess often because preferences drift.
Often confused with reinforcer assessment
A preference assessment shows which items a person chooses or engages with. A reinforcer assessment tests whether delivering an item contingent on a response actually increases that response. The top choice in a preference assessment is a strong candidate, but only its effect on behavior makes it a reinforcer.
Exam tip
Match the format to its description: two items at a time is paired-stimulus; chosen item removed is MSWO; chosen item returned is MSW; free access with timing is free-operant. If the stem says the learner reacts badly when items are taken away, free-operant is usually the best answer.
Can you spot preference assessment in a scenario?
Practice RBT B.1 with exam-style questions and instant feedback.