Using the high-probability instructional sequence to improve initiation and completion of low-probability...

This study examined the use of the high-probability (high-p) instructional sequence during pre-academic or academic activities for three young children diagnosed with autism spectrum disorder (ASD) served in public elementary schools. Specifically, we examined the effects of the high-p instructional sequence on the children's initiation and completion of low-probability (low-p) instructions, implemented by their classroom teachers. A nonconcurrent multiple-baseline design across participants was used to evaluate the intervention outcomes. The results indicated that the high-p instructional sequence may be an effective antecedent-based intervention for autistic children who typically initiate the low-p instructions but have difficulty completing the instructions. A strong magnitude of effect was shown for initiation across children. For one child, initiation and completion increased during high-p, and the improvement was maintained above criterion levels when high-p instructions in sequence were faded. For two children, we found high levels of initiation but variable performance in completion during high-p. The use of programmed reinforcement for one child suggests that for autistic children who do not often initiate the low-p instructions, the addition of programmed reinforcement may be needed to increase completion of low-probability instructions.