Using a Group Stimulus Preference Assessment to Design an Effective Group Contingency

The purpose of this study was to extend the limited research on group stimulus preference assessment (SPA) procedures. The study occurred in two sections of a middle school special education classroom and included 20 students with multi-categorical disabilities. A paired stimulus group SPA was used to identify a preference hierarchy for each class, and results were validated using single case designs in which baseline conditions were compared to group contingency conditions with alternating sessions of the highest-preferred (high-p) and lowest-preferred (low-p) consequences. Both group contingency conditions increased the percentage of students prepared for class relative to baseline; however, consistently higher levels of students were prepared for class during high-p sessions. Student responses on a daily quiz were similar in both conditions, but social validity surveys indicated students felt the most motivation and enjoyment during high-p sessions.