ABA Design Overview

Introduction

• ABA Design: Baseline-Intervention-Baseline method.
• Purpose: To determine the effect of a treatment on a target behavior.
  • Baseline phase (A): Initial observation without intervention.
  • Intervention phase (B): Implement treatment to change behavior.
  • Return to baseline (A): Withdraw treatment to observe changes.

Key Steps in ABA Design

1. Define Target Behavior and Treatment
   • Identify behavior to change and intervention method.
2. Baseline Data Collection (A Phase)
   • Collect data over a predetermined number of sessions.
   • Aim for stable baseline trends before moving to intervention.
3. Introduce Treatment (B Phase)
   • Implement treatment until a stable response in desired direction.
4. Withdraw Treatment and Return to Baseline (A Phase)
   • Monitor behavior to see if it returns to baseline levels.

Interpretation of Results

• Improvement during intervention suggests treatment efficacy.
• Return to baseline behavior post-treatment suggests treatment impact.

Example: Johnny's Case

• Subject: Johnny, a 7-year-old with on-task difficulty.
• Intervention: Verbal praise for being on-task.
• Outcome:
  • Baseline: Off-task behavior, on-task 4/20 times.
  • Intervention: Improved to 15/20 on-task observations.
  • Return to baseline: Reverted to off-task, similar to initial levels.

Considerations

• ABA vs. ABAB Design: ABAB introduces the intervention a second time to strengthen conclusions about treatment effects.
• Aim: Validate the functional relationship between the behavior and treatment.

Prediction, Verification, and Replication

Prediction

• Predict behavior outcome based on baseline trends.
• Changes in dependent variable suggest treatment effect.

Verification

• Confirm that behavior does not change without intervention.
• Observe return to baseline when intervention is removed.

Replication

• Reintroduce intervention to check for consistent treatment effects.
• Consistent change suggests treatment causality.

Graph Analysis

• First Graph: All three criteria satisfied (Prediction, Verification, Replication).
  • Clear change in behavior with intervention; return to baseline without it.
• Second Graph: Prediction and Verification satisfied, but not Replication.
  • Initial intervention changed behavior; reintroduction failed to replicate results.

Conclusion

• ABA design is useful for determining the effectiveness of interventions.
• ABAB designs help in validating the results through repetition.