Association for Behavior Analysis International

The high-probability (high-p) instructional sequence involves the presentation of high-p instructions followed by the presentation of a low-probability (low-p) instruction. Researchers have used this procedure to increase compliance across a variety of behaviours, including academic skills, social skills, medical tasks, and food acceptance. Given the broad applicability of this procedure, it is important to identify the procedural variables within the high-p instructional sequence that produce the most meaningful outcomes. The first presentation will compare 2 iterations of the high-p instructional sequence, high-p with a preferred food on a spoon and high-p with an empty spoon, to increase food consumption. The second presentation will (a) compare the effectiveness ofpraise versus edibles as the consequence for compliance with high-p instructions and (b) determine if the number of high-p instructions can be faded from 3 to fewer instructions. Both papers will be discussed within the context of clinical implications and suggestions for future research.

Graduate students

Teachers and coaches

Behavior Analysts

1. Describe the variables of the high-probability instructional sequence that influence the effectiveness.
2. Describe the application of the high-probability instructional sequence to increase food consumption
3. Describe the application of the high-probability instructional sequence within a multicomponent treatment package.

Food selectivity is defined as a child or youth refusing to eat a sufficient variety of foods based on type, texture, or other dimensions (e.g., colour, packaging). It can have a substantial negative impact on family stress, child nutrition and health, and can lead to inappropriate mealtime behaviours. The high-probability (high-p) instructional sequence is a non-intrusive procedure that involves the presentation of three high-p instructions followed by the presentation of one low-probability instruction. To date, only eight studies – with mixed findings – have examined the effectiveness of the high-p instructional sequence to increase young children's consumption of food. Therefore, the purpose of this study is to compare the effectiveness and efficiency of two iterations of the high-p instructional sequence, high-p with a preferred food on a spoon and high-p with an empty spoon, to increase food consumption in two children with autism spectrum disorder and food selectivity using a multielement design within a reversal design.

To replicate and extend previous research on the high probability request sequence, the first research question was: What are the effects of praise versus edibles as the consequence for responses to high-p requests? In a reversal design with a child with CHARGE Syndrome, there was initial but not sustained experimental control demonstrating higher responding with edibles compared to praise. The second research question was: To what extent can high-p requests be faded from 3 to fewer per low-p request? After demonstrating experimental control with 3 high-p requests, an attempt to fade to 2 high-p requests failed. In a final analysis, experimental control was demonstrated by providing varied reinforcement in the form of videos identified in presession preference assessments. In 20% of sessions, IOA was a mean of 99.1% for high-p requests (range, 93.3% to 100%) and 100% for low-p requests. Results are discussed in terms of continually assessing motivating operations.