Components of a Discrete Trial
Each discrete trial has five components: (1) the discriminative stimulus (SD) or instruction, (2) a prompt if needed, (3) the learner's response, (4) the consequence (reinforcement for correct responses, correction for errors), and (5) the inter-trial interval (ITI), a brief pause between trials. Maintaining this structure consistently is essential for effective teaching.
Implementation Best Practices
Keep instructions clear and concise. Use the same wording for the SD until the learner has mastered the skill. Deliver reinforcement immediately (within 1-2 seconds). Use the most effective reinforcers for each learner. Vary reinforcers to prevent satiation. Keep the ITI brief (3-5 seconds) to maintain instructional momentum. Intersperse mastered and acquisition targets to maintain motivation.
Data Collection During DTT
Record the response on each trial as correct (independent), prompted, or incorrect. Track the prompt level used. Calculate the percentage of independent correct responses per target per session. Graph data to monitor progress and make data-based decisions about when to advance, modify, or discontinue targets.
Common Errors
Prompt dependency: providing prompts too quickly or not fading them systematically. Inadvertent reinforcement of errors: giving attention or instruction following incorrect responses. Lack of generalization programming: teaching only in the DTT setting without planning for transfer. Satiation: using the same reinforcer repeatedly until it loses its effectiveness. Insufficient mastery criteria: moving on before the learner has demonstrated stable, independent responding.