Evaluation of the rate of problem behavior maintained by different reinforcers across preference assessments.

Kang et al. (2011) ran three kinds of preference tests with six kids who had developmental delay. They used paired stimulus, multiple-stimulus without replacement, and free operant formats. Each child also had a known function for problem behavior—attention, tangible, or escape. The team counted how often problem behavior happened during each test.

Problem behavior rates changed with the test format. The effect depended on the reinforcer that kept the behavior alive. For example, a child whose behavior was fueled by escape showed more outbursts during the free operant format than during the paired format. No single format was safest for every function.

Kok et al. (2026) pooled 270 single-case studies and found that externalizing behaviors drop during treatment but climb back up after sessions end. Soyeon’s work helps explain part of that fade-out: if we pick the wrong preference format, we may feed the very reinforcer that keeps problem behavior alive. Bitsika et al. (2015) showed that anxiety scores in ASD shift when you switch from parent to child report; Soyeon shows the same “method matters” rule applies to problem behavior during preference tests. Mammarella et al. (2022) warned that few school FBA studies measure ecological validity; Soyeon answers by flagging an internal validity threat we can control today—test format.

Before you next run a preference assessment, look up the child’s latest FBA. If escape maintains the behavior, skip free operant; if attention maintains it, avoid large-group multiple-stimulus layouts. Pick the format that gives the reinforcer less airtime. You will get cleaner data and safer sessions.