Question
Difficulty: medium. Skill: apply. Type: experimental design critique.
A BCBA is evaluating whether an intervention changed leaving the instructional area. A second program change began during the same week. Which concern best reflects internal and external validity? The case file includes 11 recent sessions, 4 implementers, and 1 setting.
ATell everyone to try harder and review the case next month
BTreat the most recent data point as proof of the final conclusion
CCheck measurement quality, observer agreement, and procedural integrity before making a major decision in relation to learner's leaving the instructional areaCorrect answer
DBase the decision on the descriptive label for leaving the instructional area and bypass internal and external validity
Explanation
Answer CThe clue is the combination of four sessions of stable baseline data followed by two overlapping intervention points, leaving the instructional area, and the required task: Internal and external validity. The case file includes 11 recent sessions, 4 implementers, and 1 setting. Check measurement quality, observer agreement, and procedural integrity before making a major decision in relation to learner's leaving the instructional area is best because it answers that clue through measurement quality and procedural integrity instead of treating the scenario as a generic behavior problem. On exam items like this, name the decision point first, then eliminate options that rely on one report, a label, a familiar protocol, or an action that skips the relevant data check.
Why this question is hard
ClueKey scenario clueThe clue is the combination of four sessions of stable baseline data followed by two overlapping intervention points, leaving the instructional area, and the required task: Internal and external validity. The case file includes 11 recent sessions, 4 implementers, and 1 setting.
TrapCommon trapVague delayed feedback does not create a measurable plan for improvement.
NextIf you missed it, review Internal validity and confoundsThen answer a few related scenarios before moving back to broad practice.
Why the other choices are weaker
AChoice AVague delayed feedback does not create a measurable plan for improvement.
BChoice BA single point rarely supports a strong conclusion without considering trend, variability, and context.
DChoice DThis is weaker because the label does not answer the Internal and external validity decision point or test Measurement quality and procedural integrity.
Study tags
Measurement quality and procedural integrityInternal and external validityvalidityreliability
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