Differential Reinforcement of Other Behavior

Selection of Target Behaviors

Several variables are critical to the successful implementation of DRO schedules. The first is the selection of target behaviors, especially when the student of concern has a large number of them in his or her repertoire. For example, if problem behaviors include swearing and hitting people, one option is to select the most problematic behavior for the DRO schedule (hitting people, in this case); this means that the student could swear during the interval and still receive reinforcement. A second option is to specify the most problematic behavior in the DRO schedule (e.g., hitting) and add that, at the end of an interval during which the most problematic behavior does not occur, the reinforcer will not be delivered until a specified number of minutes has passed without the less problematic behaviors occurring (e.g., swearing). A third option is to include both swearing and hitting in the DRO schedule, so that the student would be required to refrain from engaging in both behaviors during the interval to earn reinforcement. This makes sense, especially when the target behaviors all serve the same function for the student.

Interval Length

Based on a number of research studies, the length of the initial interval selected for the DRO schedule should be based on the interresponse time (IRT), the average length of time between problem behaviors. To calculate the IRT, one would (a) record the frequency of the target behaviors over several sessions, (b) calculate the average number of target behaviors across sessions, and (c) divide the total amount of time during baseline by the average number of behaviors. For example, imagine that Eric destroys property 2, 4, 4, 6, 3, and 5 times per hour over a 6-hour period (step a). The average number of target behaviors over the 6-hour period is 4 per hour (24 behaviors ÷ 6 hours; step b). This means that, across the entire 6 hours (360 minutes), property destruction occurred, on average, once every 90 minutes (360 minutes ÷ 4 behaviors per hour; step c). Thus, the IRT of 90 minutes would be the length of the initial interval typically used for the DRO schedule, such that Eric could earn a reinforcer every time 90 minutes passed without an episode of property destruction. Some researchers have recommended that, especially when the problem behavior presents a risk to the student or to others, the initial interval length be set at half of the IRT, to ensure that the student will come in contact with the reinforcer at least 50% of the time, based on the baseline rate. Based on the calculations shown, Eric would then earn a reinforcer each time 45 minutes passed without an episode of property destruction.

...