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Board Certified Behavior Analyst Examination

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Explained questions: 9
Subject areas: Aug 19, 2026
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Every subject area, covered

A. Behaviorism and Philosophical Foundations46 questions
B. Concepts and Principles105 questions
C. Measurement, Data Display, and Interpretation84 questions
D. Experimental Design62 questions
E. Ethical and Professional Issues114 questions
F. Behavior Assessment111 questions
G. Behavior-Change Procedures116 questions
H. Selecting and Implementing Interventions90 questions
I. Personnel Supervision and Management83 questions

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Results

Date: 19th Aug 2026Time Taken: 00:00:31

C. Measurement, Data Display, and Interpretation

Answers Result

Which functional-analysis result provides the STRONGEST experimental evidence that a particular reinforcement contingency maintains problem behavior?

Incorrect

A.Comparable high responding across test and control conditions during repeated, systematically alternated sessions
B.One unusually high value in a test condition, with substantial overlap across the remaining repeated sessions
C.Frequent responding near the suspected event during natural routines, without systematic manipulation of that event
D.Repeated separation between a test condition and the control, with the suspected contingency arranged only in the test

In a residential program, a behavior analyst reviews duration data for loud vocal episodes. Across shifts, staff begin timing when vocalizing “seems disruptive” and stop when the client “appears settled.” A supervisor reports mean episode duration by dividing each 60-minute observation by the episode count. Because treatment decisions depend on whether episodes are shortening, what should the behavior analyst address FIRST?

Correct

A.Define observable onset and offset events, time each occurrence, and divide summed occurrence durations by the number of occurrences.
B.Keep the judgment-based onset and offset rules, then divide total observation time by the number of occurrences.
C.Define only the onset event, record the count, and treat the count as sufficient evidence that episodes are shortening.
D.Time from the start of each shift to the first episode, then average those values across shifts.

A student engaged in eight to ten disruptions per class during baseline. The behavior-change plan specifies no more than two disruptions per class by the tenth intervention session. Across 10 sessions, disruptions range from five to eight without a decreasing trend. Treatment-integrity observations and independent measurement checks reveal no material concerns. The teacher reports that instruction remains substantially disrupted. What should the behavior analyst do next?

Incorrect

A.Replace event recording with a less sensitive measure because the current system shows excessive session-to-session variation.
B.Continue the intervention unchanged because the intervention values are visibly lower than the baseline values.
C.Discontinue behavior-analytic services because the behavior was not eliminated during the first 10 intervention sessions.
D.Modify the intervention because change is too small, inconsistent, and delayed to meet the criterion or produce reported benefit.

Answers Result

Which functional-analysis result provides the STRONGEST experimental evidence that a particular reinforcement contingency maintains problem behavior?

Incorrect

A.Comparable high responding across test and control conditions during repeated, systematically alternated sessions
B.One unusually high value in a test condition, with substantial overlap across the remaining repeated sessions
C.Frequent responding near the suspected event during natural routines, without systematic manipulation of that event
D.Repeated separation between a test condition and the control, with the suspected contingency arranged only in the test

A functional analysis demonstrates control by systematically arranging a suspected reinforcement contingency in a test condition and comparing responding with a control condition. Consistently greater responding in the test condition across repeated sessions supports the hypothesized behavioral function. A single extreme value does not establish a replicated pattern, naturally occurring correlations do not demonstrate experimental control, and comparable high responding across all conditions is undifferentiated rather than evidence for one contingency.

Correct

A.Define observable onset and offset events, time each occurrence, and divide summed occurrence durations by the number of occurrences.
B.Keep the judgment-based onset and offset rules, then divide total observation time by the number of occurrences.
C.Define only the onset event, record the count, and treat the count as sufficient evidence that episodes are shortening.
D.Time from the start of each shift to the first episode, then average those values across shifts.

Duration is the elapsed time from a response’s defined onset to its defined endpoint. Observable boundaries are therefore necessary for consistent timing across shifts. To obtain mean duration per occurrence, the analyst times each occurrence, sums those durations, and divides by the number of occurrences. Dividing the entire observation period by the occurrence count does not calculate average response duration. Count alone does not measure temporal extent, and timing from shift onset to the first response measures latency rather than duration.

Incorrect

A.Replace event recording with a less sensitive measure because the current system shows excessive session-to-session variation.
B.Continue the intervention unchanged because the intervention values are visibly lower than the baseline values.
C.Discontinue behavior-analytic services because the behavior was not eliminated during the first 10 intervention sessions.
D.Modify the intervention because change is too small, inconsistent, and delayed to meet the criterion or produce reported benefit.

The intervention data are somewhat lower than baseline, but they remain well above the criterion, vary across sessions, and have not produced meaningful improvement within the specified review period. With implementation and measurement concerns already checked, modification is warranted. A visible decrease alone does not establish sufficient benefit. Elimination was not the goal, so discontinuing all services for failure to reach zero is unwarranted. Using a less sensitive measure would impair evaluation rather than correct the inadequate outcome.

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BCBA questions test how you apply knowledge in real situations. After every answer, you are provided with a clear rationale so you can understand the reasoning, learn from mistakes, and recognize it when it appears again.

Question 1 of 3

Which functional-analysis result provides the STRONGEST experimental evidence that a particular reinforcement contingency maintains problem behavior?

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Every subject area, covered

Understand why,not only what.

Study anywhere, on any device

Pick up on the web

Take it in your pocket

Every answer shapes what you study next.

Practice

Understand

Focus

Improve

Before you start,you probably want to know…

Are the questions on practice exams like the ones on the real BCBA?

How is this different from a prep book?

How long do I need to prepare?

Can I study on my phone?

What happens if I don't pass?

Understand why,
not only what.

Before you start,
you probably want to know…