Reversal, Multiple-Baseline, Multielement, Changing-Criterion Designs
Key Takeaways
- Reversal designs show control by introducing and withdrawing or alternating conditions in sequence.
- Multiple-baseline designs show control through staggered intervention across behaviors, settings, or participants.
- Multielement designs compare conditions rapidly and are useful when behavior can contact alternating contingencies.
- Changing-criterion designs show control when behavior tracks stepwise criterion changes.
Core designs and when to use them
A reversal design, such as ABAB, compares behavior when the intervention is absent and present. It is powerful when behavior is reversible and withdrawal is ethical. It is weak when the behavior cannot return to baseline, when withdrawal would be unsafe, or when learning produces lasting change.
A multiple-baseline design staggers intervention across participants, settings, or behaviors. It is useful when reversal is unethical or impossible. Experimental control is shown when each tier changes only after intervention is introduced, while untreated tiers remain near predicted baseline patterns.
A multielement design rapidly alternates two or more conditions. It is efficient for comparing interventions or assessment conditions. It requires clear discrimination between conditions and attention to possible carryover or multiple treatment interference.
A changing-criterion design evaluates whether behavior changes in a stepwise pattern as criteria are adjusted. It is useful for gradual behavior change, such as increasing task completion or reducing response rate. Each criterion level should be distinct enough to detect behavior tracking.
| Design | Best fit | Main caution |
|---|---|---|
| Reversal | Reversible behavior and ethical withdrawal | Withdrawal may be harmful or impossible |
| Multiple baseline | Nonreversible skills or unsafe withdrawal | Tiers must be independent enough |
| Multielement | Rapid comparison of conditions | Carryover and poor discrimination |
| Changing criterion | Gradual shaping of performance | Criteria must be achievable and meaningful |
Fast selection rules
Use reversal when you can safely turn the independent variable on and off. Use multiple baseline when withdrawal is not acceptable. Use multielement when the question is which condition works better. Use changing criterion when the target is progressive movement toward a terminal level.
A BCBA teaches three unrelated self-care skills. Because withdrawing instruction after skill acquisition would be inappropriate, the BCBA staggers intervention across skills. Which design is most appropriate?
A BCBA compares attention, escape, tangible, and alone conditions in quick alternation during a functional analysis. Which design logic is being used?
A learner currently completes 2 math problems independently. The BCBA sets criteria of 4, 6, 8, and 10 problems and changes reinforcement as each criterion is met. Which design best fits?