Using Conditional Percentages During Free-Operant Stimulus Preference Assessments to Predict the Effects of Preferred Items on Stereotypy: Preliminary Findings.

The team ran a free-operant competing stimulus assessment (CSA) with four clients. They watched which items the kids touched most and how much stereotypy happened at the same time.

They tried three lengths: 10 minutes, 30 minutes, and a full 30-minute single test. The goal was to find high-preference, low-stereotypy (HP-LS) items that still worked when time was cut.

All four kids showed the same HP-LS items in the short 10-minute test as in the long ones. When those items were given later, stereotypy dropped every time.

A 10-minute CSA was enough to spot the item that would later cut automatically maintained stereotypy.

Conine et al. (2021) also asked if shorter is okay. They saw that one-session and two-session MSWO lists look like the full three-session list, but the very top item can change. Perez et al. (2015) show the CSA top item stays the same even at 10 minutes, giving you more confidence to trim time.

Hastings et al. (2001) used a 30-second single-stimulus engagement test to predict reinforcer power. Perez et al. (2015) extend that idea: brief engagement time also predicts which item will block stereotypy, not just which item will reinforce.

Lemons et al. (2015) speed up paired-stimulus tests by picking whole categories. Perez et al. (2015) take a different shortcut: keep the free-operant method but stop at 10 minutes. Both groups aim to save time without losing accuracy.

You can run a CSA during a single short break and still pick the right toy or tablet to lower stereotypy. Try a 10-minute session, mark the item with high engagement and almost no stereotypy, then use it in treatment. You save precious therapy minutes while keeping the same benefit.