20 free BCBA practice questions

Correct answer: A · Parsimony: rule out simpler explanations before more complex ones

Parsimony favors the simplest explanation that accounts for the facts, so simple, observable accounts are ruled out before complex or hypothetical ones are considered. Checking the change in reading level before accepting a hypothetical inner cause does exactly that. Task A.2 of the BCBA Test Content Outline (6th ed.) lists selectionism, determinism, empiricism, parsimony, and pragmatism as assumptions candidates should explain. Selectionism holds that consequences select behavior across a lifetime, a species, and a culture; it says nothing about which explanation to test first. Pragmatism judges an account by whether it works in practice. Determinism, the assumption that behavior is lawful, is something the BCBA also accepts, but it does not tell her to test the simpler explanation before the complex one.

Look for this next time: Parsimony: rule out simpler, observable explanations before turning to complex or hypothetical ones.

Correct answer: D · An establishing operation that raises water's value and evokes asking

Water deprivation is an unconditioned motivating operation with two effects: a value-altering effect, making water a more effective reinforcer, and a behavior-altering effect, evoking behavior such as asking that has produced water before. An MO that increases both is an establishing operation (Laraway, Snycerski, Michael, and Poling, 2003). A discriminative stimulus works differently: it signals that a response is likely to be reinforced, while the MO sets how valuable that reinforcer is. Telling the two apart is task B.17 of the 6th-edition outline. An abolishing operation, such as drinking a large amount, would lower both the value of water and the asking. Deprivation is a condition, not a stimulus that follows a response, so it is not a conditioned reinforcer.

Look for this next time: A motivating operation changes how much a reinforcer is worth; a discriminative stimulus signals whether it is available.

Correct answer: C · A mand first, then a tact

Skinner's Verbal Behavior (1957) classifies verbal operants by their controlling variables, not by their form. The first “juice” occurs under a motivating operation, two hours without a drink, and is followed by the specific item it names, so it is a mand. The second is evoked by a nonverbal stimulus, the drawing, and is followed by generalized conditioned reinforcement, praise, so it is a tact. Reversing the order gets both controlling relations backward. An intraverbal is controlled by a verbal stimulus without point-to-point correspondence, such as answering “What do you drink at snack?”, and an echoic repeats a spoken model; neither fits. The same word can belong to different operants, which is why “a mand both times” is wrong. Task B.19 of the outline asks candidates to make this distinction.

Look for this next time: Classify a verbal operant by what controls it and what follows it, not by the word spoken.

Correct answer: A · Respondent extinction: the CS is presented repeatedly without the US

The bite, an unconditioned stimulus, turned the sight of dogs into a conditioned stimulus that elicits trembling and a racing heart. Presenting the conditioned stimulus again and again without the unconditioned stimulus weakens the conditioned response, which is respondent extinction, part of task B.11 of the 6th-edition outline. Habituation, as behavior analysts use the term, is a decline in an unconditioned response to an unconditioned stimulus that is presented repeatedly; dogs did not elicit fear before the bite, so this response was learned. Operant extinction would require that the responses had been reinforced by a consequence, such as attention, that is then withheld; the stem describes elicited responses and no such contingency. Negative punishment removes a stimulus after a response, and nothing is removed after a response here.

Look for this next time: Respondent extinction: present the conditioned stimulus repeatedly without the unconditioned stimulus until it stops eliciting the response.

Correct answer: B · Scored-interval IOA, about 56%

Intervals scored by at least one observer: 6 + 8 − 5 = 9. Intervals neither scored: 20 − 9 = 11. Scored-interval IOA uses only intervals in which at least one observer scored the behavior: 5 ÷ 9 × 100 ≈ 56%. Interval-by-interval IOA uses every interval: (5 + 11) ÷ 20 × 100 = 80%, and for a low-rate behavior the many intervals neither observer scored inflate that figure. Cooper, Heron, and Heward (2020) recommend scored-interval IOA for low-rate behavior and unscored-interval IOA for high-rate behavior. Unscored-interval IOA is 11 ÷ 15 × 100 ≈ 73%, where 15 is the number of intervals that at least one observer left unscored. Total count IOA, 6 ÷ 8 × 100 = 75%, compares totals and cannot show that the observers scored the same intervals.

Look for this next time: For low-rate behavior, scored-interval IOA avoids the inflation that unscored intervals add to interval-by-interval agreement.

Correct answer: D · Continue baseline and look for the sources of the variability first

Baseline logic depends on steady-state responding: a stable baseline lets the analyst predict what would happen without intervention, so a later change can be credited to the intervention. With values swinging from 2 to 15, almost any treatment data could fall inside the baseline range, and the mean of 7.8 ((4 + 15 + 2 + 12 + 6) ÷ 5) hides that spread. Cooper, Heron, and Heward (2020) advise continuing baseline until responding is stable and, when variability persists, looking for the variables that produce it, such as differences between class periods, rather than averaging it away. Because the behavior is not dangerous, waiting is reasonable. Weekly averages hide the session-to-session variability that needs analysis, and a bar graph of the mean discards the time series that visual analysis needs (task C.11).

Look for this next time: Before intervening on a behavior that is not dangerous, extend a highly variable baseline and look for what drives the variability.

Correct answer: B · A multiple-baseline design across three sets of words

Reading learned sight words is an irreversible behavior: it should not return to baseline levels when teaching stops, so a reversal design could not show the needed reversal, and withdrawing effective teaching would be hard to justify. A multiple-baseline design across behaviors introduces the procedure to one word set at a time while the other sets stay in baseline; control is shown when each set improves only after the procedure reaches it, through prediction, verification, and replication across tiers. A multielement design that alternates teaching and no-teaching sessions on the same words cannot separate the conditions, because words learned in teaching sessions are still read correctly in the other sessions. An AB design shows change but no replication, so practice or maturation could explain it. Task D.7 covers these designs.

Look for this next time: For irreversible behavior such as learned skills, use a multiple-baseline design instead of a reversal.

Correct answer: C · Decline it kindly, restate the rule, and welcome a thank-you note

Standard 1.12 of the BACB Ethics Code for Behavior Analysts says behavior analysts do not give gifts to or accept gifts from clients, stakeholders, supervisees, or trainees worth more than US $10, and that they explain this at the start of the professional relationship, as this BCBA did. The standard adds that an acceptable gift is an infrequent expression of gratitude that brings no financial benefit to the recipient, which a card or note can be. A $50 gift card is over the limit however sincere the father is. Sharing it with the RBTs still accepts an over-limit gift, now for the team. Recording its value documents the gift but does not make it acceptable. Declining warmly and restating the rule protects both the relationship and the standard.

Look for this next time: Under Ethics Code standard 1.12, decline gifts worth more than US $10, however sincere, and restate the rule kindly.

Correct answer: A · Decline to solicit it, and explain to the team why the Code bars it

Standard 5.07 of the BACB Ethics Code for Behavior Analysts says behavior analysts do not solicit testimonials from current clients or stakeholders for advertisements designed to obtain new clients, because of the possibility of undue influence and implicit coercion. The mother's eagerness and a signed release do not remove that risk, since her son still depends on the clinic's services. Blurring faces addresses identification, not solicitation. The standard also says that when an employing organization violates it, the behavior analyst makes reasonable efforts to remediate the situation and documents those efforts, so handing the job to marketing staff does not end her responsibility. Standard 5.08 sets separate conditions for solicited testimonials from former clients, including clear disclosures and the right to rescind.

Look for this next time: Do not solicit current clients' testimonials for advertising (standard 5.07), even when a caregiver volunteers.

Correct answer: D · Inform the relevant parties, correct the claims, and document each step

Standard 2.06 of the BACB Ethics Code for Behavior Analysts says that when inaccuracies in reporting or billing are discovered, behavior analysts inform all relevant parties, such as organizations, licensure boards, and funders, correct the inaccuracy in a timely manner, and document all actions taken and the outcomes. Standard 1.01 adds that they correct inaccurate submissions as soon as they become aware of them. Who or what caused the error does not matter; once she knows, leaving paid claims for sessions that never happened is not acceptable. Withholding future billing does not correct the original claims and creates a second inaccuracy. An internal fix leaves the funder's records wrong. The exact correction process, such as a voided or adjusted claim, follows the funder's rules.

Look for this next time: When a billing error surfaces, inform the relevant parties, correct it with the funder promptly, and document each step.

Correct answer: C · Automatic reinforcement is likely; a series of alone sessions can test it

In the functional analysis model introduced by Iwata and colleagues (1982/1994), the test conditions are compared with a play (control) condition. When a behavior occurs at similar high rates in every condition, including alone, where no social consequences are available, the results are undifferentiated, and the usual interpretation is automatic reinforcement: the response produces its own reinforcer. A series of consecutive alone sessions can check this, because socially maintained behavior tends to decline when no one is present, while automatically reinforced behavior persists. High rates in the attention or demand condition mean little when rates are just as high in the play condition. “No function” is not a conclusion behavior analysis draws, since operant behavior is maintained by some reinforcer. Task F.6 covers designing and evaluating functional analyses.

Look for this next time: High, undifferentiated rates across all conditions, including alone, point to automatic reinforcement; extended alone sessions can test it.

Correct answer: A · The data show correlations; a functional analysis can test the function

Descriptive assessments such as ABC recording show which events tend to occur with a behavior, not which events cause it. Here a likely motivating operation for escape (independent math) and a possible reinforcer (reprimands) both appear, and reprimands may follow call-outs simply because teachers respond to disruptions. A functional analysis manipulates conditions and consequences directly, so it can show which variable controls the behavior. Escape is not ruled out: a reprimand can interrupt or delay work even when the student stays in the room. A punisher, by definition, decreases future behavior, so a consequence that follows a behavior that keeps occurring is more likely a reinforcer or neutral, not a punisher. Tasks F.5 and F.6 of the outline cover descriptive assessments and functional analyses.

Look for this next time: Descriptive data reveal correlations; a functional analysis shows which variable actually maintains the behavior.

Correct answer: B · Recommend a prompt medical evaluation and document the referral

A sudden onset with no history, a pattern tied to night and eating, and ear tugging all suggest a possible medical cause, such as ear pain. Standard 2.12 of the BACB Ethics Code for Behavior Analysts says behavior analysts ensure, to the best of their ability, that medical needs are assessed and addressed when there is any reasonable likelihood that a referred behavior is influenced by medical or biological variables, and that they document the referral and follow up with the client. Task F.7 of the outline covers interpreting assessment information to decide when referral to others is needed. A functional analysis, a DRO, or extinction may be useful later, but starting any of them first risks leaving pain untreated and treating its effects as if social reinforcement maintained them.

Look for this next time: Self-injury with a sudden onset and signs of pain calls for a medical referral first (standard 2.12), before function-based treatment.

Correct answer: D · Full-session DRL, reinforcing when questions stay at or below a limit

Differential reinforcement of low rates (DRL) is used when a behavior is acceptable but occurs too often. In full-session DRL, reinforcement follows a session in which the number of responses is at or below a criterion, here 5 per class, and the criterion can be lowered gradually from the baseline rate (Deitz and Repp, 1973). DRO delivers reinforcement for the absence of the behavior during intervals, which would push questions toward zero, the opposite of the teacher's goal. DRA reinforces a different behavior, such as writing questions down, which would replace asking rather than moderate it. DRH increases a behavior that occurs too rarely. Task G.2 of the outline asks candidates to design and evaluate these forms of differential reinforcement.

Look for this next time: Use DRL when a behavior is acceptable at a lower rate; DRO aims for its absence.

Correct answer: B · Constant time delay

Constant time delay begins with 0-second delay trials, in which the prompt follows the instruction immediately, and then inserts one fixed delay, here 4 seconds, that stays the same on every later trial. The learner can respond before the prompt, and correct responses before it are reinforced, so stimulus control transfers from the model to the coin. Progressive time delay increases the delay gradually, for example by 1 second at a time across trials or sessions. Least-to-most prompting gives the least intrusive prompt first and moves to more intrusive prompts after errors or no response. Graduated guidance adjusts physical guidance moment to moment during a response. Task G.8 of the outline names prompt delay among the procedures for fading prompts.

Look for this next time: Constant time delay: start with 0-second trials, then use one fixed delay before the prompt on every trial.

Correct answer: A · Time-out removes him from the task, so it likely reinforces tearing

Time-out from positive reinforcement works only when the time-in setting is more reinforcing than time-out. Here time-out removes the student from a task he likely finds aversive, so tearing produces escape, and a behavior that rises for weeks after a consequence is being reinforced, not punished: the pattern fits negative reinforcement. Cooper, Heron, and Heward (2020) caution that time-out can function this way when it ends demands, and task G.17 of the outline covers evaluating punishment procedures, including time-out. Time-out is negative punishment by design, not positive punishment, and lengthening it would only extend the escape. An extinction burst is a brief increase when reinforcement is withheld; here escape follows every tear, and the rise has lasted three weeks. Nothing in the stem suggests automatic reinforcement.

Look for this next time: If behavior rises under time-out from a demanding task, suspect escape: time-out may be negatively reinforcing it.

Correct answer: C · Retrain staff to criterion and monitor integrity before judging the plan

A plan carried out correctly only about half the time has not really been tested, so its lack of effect says little about the plan itself. Task H.6 of the outline asks candidates to make data-based decisions about procedural integrity. Retraining staff, for example with behavioral skills training, until they meet an integrity criterion, and then continuing to measure integrity, shows whether the plan works as written. Standard 2.18 of the BACB Ethics Code for Behavior Analysts calls for assessing the situation and taking corrective action when desired outcomes are not realized. Adding punishment skips that step and conflicts with standard 2.15, which reserves restrictive or punishment-based procedures for when less intrusive means have not worked. A new plan may fail for the same reason, and waiting longer without fixing integrity only delays the answer.

Look for this next time: When integrity is low, fix implementation and measure it again before concluding that an intervention does not work.

Correct answer: B · Saying “break” to get a brief pause from brushing

Functional communication training replaces problem behavior with a communication response that produces the same reinforcer (Carr and Durand, 1985). Because the aggression is maintained by escape, the replacement must also produce escape, at first a brief, immediate pause, so that it competes with aggression; brushing time can then be increased by gradually raising how much brushing comes before a break. Asking for a toy produces a different reinforcer, a tangible, and does not meet the escape function. Sitting quietly for two minutes is a goal, not a functionally equivalent response, and it gives the child no way to request the escape he is working for. Pointing to a toothbrush picture names the activity rather than requesting a break. Task H.3 of the outline covers selecting socially valid alternative behavior.

Look for this next time: In functional communication training, the replacement response must produce the same reinforcer as the problem behavior.

Correct answer: D · Arrange regular review of the sheets with feedback

The Performance Diagnostic Checklist–Human Services (PDC-HS; Carr, Wilder, Majdalany, Mathisen, and Strain, 2013) sorts performance problems into four areas: training; task clarification and prompting; resources, materials, and processes; and performance consequences, effort, and competition. She performs accurately when observed, so she has the skill and retraining is not needed. She can describe the task, so clarification is not the issue, and sheets are always available, so resources are not either. What is missing is any consequence for completing the sheets, so a consequence-based intervention, such as scheduled review with feedback and praise, matches the assessment. Task I.6 of the outline covers function-based approaches such as performance diagnostics, and standard 4.08 of the BACB Ethics Code calls for ongoing performance monitoring and timely feedback.

Look for this next time: Match the staff intervention to the cause: when skills and materials are in place but nothing follows the task, fix the consequences.

Correct answer: C · The RBT rehearses the steps while the BCBA gives feedback, to criterion

Behavioral skills training has four components: instructions, modeling, rehearsal, and feedback, repeated until the trainee meets a performance criterion (Parsons, Rollyson, and Reid, 2012). Instructions and modeling are done, so the next step is rehearsal, in role-play or with a client under supervision, followed by immediate, specific feedback. Sending the RBT to work alone skips the steps that build and check the skill, and standard 4.09 of the BACB Ethics Code says behavior analysts delegate tasks only after confirming that supervisees can perform them competently. A written quiz measures knowledge of the steps, not the ability to perform them. More video models add exposure without practice, and feeling confident is not a performance criterion. Task I.5 of the outline lists modeling, practice, and feedback among performance management procedures.

Look for this next time: Behavioral skills training runs instructions, modeling, rehearsal, and feedback until the trainee performs to a set criterion.