BCB common mistakes
BCB · Understand the traps and how to avoid them.
Choosing the answer that matches the textbook label for a procedure (e.g., "extinction") without checking whether the scenario's described contingencies actually meet that definition, such as whether reinforcement was truly withheld versus merely reduced or delayed.
Candidates pattern-match on familiar keywords in the stem and stop reading the contingency details; exam items deliberately embed near-miss definitions (extinction vs. NCR, DRA vs. DRI) to test definitional precision.
What to do instead
Before selecting, restate the item's contingency in your own words as an A-B-C statement and check it against the formal definition of each candidate answer; eliminate any option whose defining feature is absent from the stem.
Treating a behavior's topography (what it looks like) as the defining property when the item hinges on function, or vice versa, and selecting a function-based intervention for a behavior whose function was never assessed in the scenario.
Topography is concrete and easy to visualize, so it anchors attention; candidates also assume the function they would expect from experience rather than the function evidenced in the stem.
What to do instead
Ask explicitly: does the stem provide functional assessment data (e.g., differential responding across conditions, attention contingent on behavior)? If not, choose the option that describes assessing function rather than assuming one.
Calculating response rate, percentage of intervals, or interobserver agreement from raw tallies without first converting to the correct unit (e.g., dividing by observation time for rate, dividing agreements by total intervals for percentage) and without checking whether the item asks for occurrence or nonoccurrence agreement.
Numbers in stems invite arithmetic; candidates rush to divide and skip confirming which formula the item requests, and IOA formulas look interchangeable under time pressure.
What to do instead
Write the formula down before computing, label the numerator and denominator in the stem data, and for IOA items explicitly identify whether the item specifies occurrence, nonoccurrence, or total agreement before choosing.
Reading a cumulative record or graph as if slope, level, and trend were interchangeable, and concluding a treatment "worked" from a change in level while ignoring an unchanged or worsening trend within condition.
Level changes are visually salient and appear immediately after phase lines, so candidates attribute the change to the intervention without inspecting within-phase trend or variability.
What to do instead
For every graph item, describe three things aloud in order: level, trend, and variability within each phase, then compare across the phase change; reject any conclusion not supported by all three.
Judging an experimental design as demonstrating a functional relation when the baseline was not stable, the change coincided with an extraneous event, or only one demonstration of effect occurred in a design requiring replication (e.g., calling a single AB comparison an experimental analysis).
Candidates equate "behavior changed after treatment started" with experimental control and overlook threats to internal validity embedded in the vignette.
What to do instead
Check the design against its replication requirement (reversal, multiple baseline tiers, alternating conditions) and scan the stem for confounds such as staff changes or concurrent events; if either is missing, the correct answer is usually the one naming the limitation.
Selecting the least restrictive or most convenient option when the scenario describes a risk, a consent gap, or a dual relationship, instead of identifying the ethically required action such as obtaining informed consent, consulting, or escalating.
Candidates optimize for client comfort or case practicality, and ethical vignettes are written so the compliant answer sounds cumbersome while the violating answer sounds reasonable and efficient.
What to do instead
Filter options through a fixed checklist: consent documented, competence and scope of practice, least restrictive effective procedure, risk-benefit, and supervision or consultation as needed; eliminate any option that skips a required step even if it produces a good outcome.
Designing or endorsing a behavior-reduction plan without a functionally equivalent replacement behavior, or writing a plan whose reinforcement schedule for the replacement is thinner than the schedule maintaining the problem behavior.
The stem emphasizes reducing the target behavior, and candidates focus on the reduction procedure while treating the replacement as optional boilerplate.
What to do instead
For any reduction item, verify three components are present: a functionally matched replacement, reinforcement for that replacement that competes with the problem-behavior contingency, and a plan for monitoring; choose the option that includes all three.
Confusing indirect and descriptive assessment methods with functional analysis, and answering that a functional analysis was conducted when the scenario describes a questionnaire, interview, or unstructured observation.
All are "functional assessment" in casual usage, and candidates collapse the category instead of distinguishing informant-based, descriptive, and experimental methods.
What to do instead
Classify the method by its defining feature: informant report (no direct observation), descriptive (direct observation, no manipulation), experimental (systematic manipulation of antecedents and consequences); match the answer to the method actually described.
Recommending a punishment-based or restrictive procedure as a first-line intervention, or one that has not been shown effective for the behavior's function, when a reinforcement-based alternative is available in the options.
Restrictive procedures appear decisive and fast, and candidates sometimes select them when the stem describes severe behavior without noting that less intrusive options were tried or that the function supports them.
What to do instead
Default to reinforcement-based, function-matched options unless the stem establishes that less intrusive procedures failed, risk justifies escalation, and consent and oversight are in place; only then select the restrictive option.
Answering supervision items by choosing to "tell the supervisee what to do" or to take over the case, rather than selecting the behavior-analytic supervisory response such as modeling, rehearsal with feedback, or arranging direct observation of the supervisee's performance.
Candidates equate supervision with advice-giving and overlook that the exam tests performance-based supervision and the supervisor's responsibility for the supervisee's client-facing behavior.
What to do instead
For supervision items, prefer options that specify observable supervisor behavior (observation, modeling, rehearsal, feedback, documentation of competence) and that keep accountability with the supervisor; reject options that are purely verbal instruction with no performance check.