Predicting the relative efficacy of three presentation methods for assessing preferences of persons with developmental disabilities.

Choices were presented to 9 individuals with developmental disabilities using a two-choice format. Each pair of items, selected based on prior preference assessment, was presented to each participant in three conditions (actual items, pictures of the items, and spoken-name presentation) using a reversal design. The evaluation was conducted using food items, and was then repeated using nonfood items. The participants were also given a test to measure their skills on discrimination tasks ranging in difficulty from simple to conditional discriminations. The participants' abilities to make consistent choices with food and nonfood items were predicted, with 94% accuracy, by their discrimination skills. The findings suggest that presentation methods can affect the accuracy of a choice assessment, and that the systematic assessment of basic discrimination skills can be used to predict the effectiveness of different presentation methods in this population.