BACB Experimental Design and Research 1 — Questions and Answers
Question 1: Which experimental design feature in single-subject research demonstrates experimental control by showing that behavior changes only when the independent variable is applied?
- Replication of effect (Correct answer)
- Random assignment
- Group comparison
- Parametric statistics
Correct answer: Replication of effect
Replication of effect within and across participants demonstrates experimental control by showing the behavior reliably changes when the independent variable is introduced and reverses when it is removed.
Question 2: In an ABAB reversal design, what does the second 'A' phase demonstrate?
- A new intervention is added
- The behavior returns toward baseline when the intervention is removed, demonstrating experimental control (Correct answer)
- Generalization has occurred
- A follow-up is conducted
Correct answer: The behavior returns toward baseline when the intervention is removed, demonstrating experimental control
The second A phase (return to baseline) demonstrates experimental control by showing that behavior reverts when the independent variable is withdrawn, ruling out coincidental factors.
Question 3: Which design introduces the independent variable to different behaviors, participants, or settings at staggered time points to demonstrate experimental control without reversing treatment?
- Reversal design
- Alternating treatments design
- Multiple baseline design (Correct answer)
- Changing criterion design
Correct answer: Multiple baseline design
A multiple baseline design introduces the intervention sequentially across baselines (behaviors, settings, or participants), demonstrating control without requiring a reversal of treatment.
Question 4: Which single-subject design is most appropriate for evaluating the relative effectiveness of two or more interventions in rapid succession?
- Multiple baseline design
- Reversal (ABAB) design
- Changing criterion design
- Alternating treatments design (Correct answer)
Correct answer: Alternating treatments design
The alternating treatments design (ATD) rapidly alternates two or more conditions within or across sessions, allowing comparison of intervention effects under similar conditions.
Question 5: In a changing criterion design, experimental control is demonstrated when behavior matches what?
- The original baseline level at each phase
- Each successive performance criterion specified in the design (Correct answer)
- The behavior of a matched control participant
- A normative performance standard
Correct answer: Each successive performance criterion specified in the design
In a changing criterion design, experimental control is shown when behavior steps up (or down) to match each new criterion level as it changes across phases.
Question 6: What is the primary internal validity threat that a multiple baseline design controls for?
- Carryover effects between treatments
- Maturation and history confounds addressed by staggered baselines (Correct answer)
- Observer drift in data collection
- Schedule thinning effects
Correct answer: Maturation and history confounds addressed by staggered baselines
Multiple baseline designs control for history and maturation by staggering intervention introduction; if improvement occurs only when the treatment is applied to each baseline, extraneous factors are ruled out.
BACB Experimental Design and Research 1
Which experimental design feature in single-subject research demonstrates experimental control by showing that behavior changes only when the independent variable is applied?