Question
Difficulty: medium. Skill: apply. Type: experimental design critique.
A decrease in leaving the work area occurs during the same week that staff change prompts, reinforcement, and session length. Across 4 sessions in service week 16, one observer recorded 21 minutes of observation in the early intervention clinic. Before claiming the intervention caused the change, the BCBA should:
AUse a simple pre-post comparison and describe any improvement as experimental control.
BWithdraw an effective safety procedure to make the graph easier to interpret.
CReview level, trend, variability, overlap, and implementation notes before deciding whether the data support a change.Correct answer
DStart several changes at once and attribute later improvement to the preferred component.
Content quality status
machine gate passedOrigOriginal study itemThis question was created for BCBA Scenario Tutor. It is not an official, leaked, or copied BACB exam question.
ChkAutomated validation passedThe item includes an answer key, explanation, wrong-choice notes, domain label, concept tags, and source notes. Automated checks cover structure, coverage, and consistency only. No named, credential-verifiable BCBA external review has occurred, and this is not a clinical or exam-validity certification.
DateLast machine check: 2026-07-05Source note: Original v2 item upgraded from internal task/concept map; not copied from official or commercial question banks.
Explanation
Answer CThe decision point is: Does the answer protect experimental control and avoid unsupported causal claims? This item specifically tests Single-case design data critique and interpretation through a data-review-scenario format. The key clue is in the stem facts: A decrease in leaving the work area occurs during the same week that staff change prompts, reinforcement, and session length. Across 4 sessions in service week 16, one observer recorded 21 minutes of observation in the early intervention clinic. Before claiming the intervention caused the change, the BCBA should: Answer C is strongest because it follows this rule: Review level, trend, variability, overlap, and implementation notes before deciding whether the data support a change. It fits the source-backed rule without announcing that rule in the stem. The tempting mistake is to choose a shortcut before the scenario's prerequisite is satisfied. This choice weakens the data basis for the decision. A defensible answer must check whether the measurement, observation, or visual-analysis evidence supports the next step. Exam move: name the missing prerequisite first, then eliminate answers that jump to a label, a familiar procedure, a single data point, or an undocumented action.
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Why this question is hard
ClueKey scenario clueA decrease in leaving the work area occurs during the same week that staff change prompts, reinforcement, and session length. Across 4 sessions in service week 16, one observer recorded 21 minutes of observation in the early intervention clinic. Before claiming the intervention caused the change, the BCBA should:
TrapCommon trapThis choice weakens the data basis for the decision. A defensible answer must check whether the measurement, observation, or visual-analysis evidence supports the next step.
NextIf you missed it, review Visual analysis and data-based decisionsThen answer a few related scenarios before moving back to broad practice.
Exam-style review notes
Structured study guidance maintained by Bifang Studio's internal editors and automated quality checks.
RuleSingle-case design data critique and interpretation: Visual analysis and data-based decisionsDoes the answer protect experimental control and avoid unsupported causal claims?
ClueWhat the stem gives youA decrease in leaving the work area occurs during the same week that staff change prompts, reinforcement, and session length. Across 4 sessions in service week 16, one observer recorded 21 minutes of observation in the early intervention clinic. Before claiming the intervention caused the change, the BCBA should:
TrapCommon trapDeclare the plan effective immediately. This often shows up as making permanent decisions from one or two data points..
FixIf you missed this itemRewrite the miss as a rule: "When I see Visual analysis and data-based decisions, I must identify the relevant evidence before choosing the action." Then answer two related D domain questions without reading explanations first.
NextNext drillPractice 3 more questions tagged to Visual analysis and data-based decisions, then explain why each wrong answer is weaker before moving back to mixed practice.
Source-aware internal editorial maintenance using src-bacb-bcba-tco-6ed for study organization; not an official BACB item and not externally reviewed by a named, verifiable BCBA.
Why the other choices are weaker
AChoice AThis choice weakens the data basis for the decision. A defensible answer must check whether the measurement, observation, or visual-analysis evidence supports the next step.
BChoice BThis choice weakens the data basis for the decision. A defensible answer must check whether the measurement, observation, or visual-analysis evidence supports the next step.
DChoice DThis choice is weaker because it does not resolve the key prerequisite in the scenario: a decrease in leaving the work area occurs during the same week that staff change prompts, reinforcement, and session length. Across 4 sessions in service week 16, one observer recorded 21 minutes of observation in the early intervention clinic. Before claiming the intervention caused the change, the BCBA should:
Study tags
Visual analysis and data-based decisionsSingle-case design data critique and interpretationleveltrend
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Machine quality gatePublished by Bifang Studio. Content is maintained by internal editors with automated structure, coverage, and consistency checks. No content has been externally reviewed by a named, credential-verifiable BCBA; these checks do not certify clinical quality or exam validity.