Evaluating the predictive validity of a single stimulus engagement preference assessment.

Four adults with developmental disabilities watched one item at a time for 30 seconds. Staff timed how long each person looked at or touched the item.

After the watching round, the same items were used as rewards in a simple task. The team wanted to see if longer watching time meant the item would work better as a reinforcer.

For all four people, the items they watched longest did work best as rewards. The single-stimulus test predicted reinforcer strength.

The order of best-to-worst items changed a little each time they repeated the test. The paired-stimulus method gave more stable rankings.

Ford et al. (2022) later used the same single-item watch test with older women who have dementia. They also found it predicted engagement better than asking clients to pick between two pictures.

Butler et al. (2021) tracked preferences for twelve months. They showed edible items stay stable longest, while leisure and social items shift more. This backs up P et al.’s note that rankings move around.

Wilson et al. (2024) kept the paired format but swapped pictures for videos. Video mode gave the steadiest hierarchy, again showing that how you show the item affects stability.

If your client avoids or fails multi-item choice tasks, try a 30-second single-stimulus engagement test. Watch and time how long they interact with each item. Use the top three as reinforcers, but re-check every few weeks since ranks can drift. For quickest prep, stick with edible items—they hold their value longer than toys or praise.