Early intensive behavioural interventions for children diagnosed with autism spectrum disorder follow different clinical models. A main component of most of these models is some form of stimulus preference assessment to identify stimuli preferences. An effective assessment of preferred stimuli allows for fluent skill-acquisition and effective mand training, as well as efficient behavior reduction programs.

The purpose of the current study was to evaluate the effectiveness of a free-operant preference assessment on the establishing operations governing mands emitted by a 5-year old girl diagnosed with autistic spectrum disorder. During baseline, the participant emitted mands only for potato chips. The independent variable consisted of a Free-operant preference assessment as described by Roane et al. (1998). At post-intervention, the participant reached a cumulative repertoire of 73 different mands. Results suggest that the exposition to new stimuli via regular Free-operant preference assessment procedures might enhance establishing operations to interact with new items, therefore increasing the opportunities to teach an enhanced mand repertoire. Based on these results, a frequent Free-operant preference assessment could be recommended to applied behaviour professionals concerned with increasing communication.