C.1: Create operational definitions of behavior.
Free practice questions for this part of the BCBA, with an explanation for every option.
A BCBA is writing a target behavior definition for a 7-year-old referred for 'aggression' in a general education classroom. Which definition is the best operational definition?
- A. Any instance of Jace hitting, kicking, or pushing another person with enough force to make contact, excluding high-fives and sanctioned contact during PE games.Correct. It names observable topographies, gives a contact criterion, and states clear exclusions, so two observers could score it the same way.
- B. Jace's tendency to act out physically when he does not get his way.Incorrect. A 'tendency' is a trait label, not a behavior, and 'act out' does not say what to count.
- C. Any time Jace becomes angry and takes out his frustration on peers or staff.Incorrect. 'Angry' and 'frustration' refer to internal states that cannot be observed directly, so observers would have to infer them.
- D. Any behavior by Jace that the teacher judges to be aggressive or disruptive to the class.Incorrect. It depends on the teacher's subjective judgment and lumps in disruption, so the definition is neither objective nor clear.
A client leaves the designated area in several ways: running out the door, crawling under a fence, and walking away during transitions. Each response gets him access to the playground. The BCBA writes one definition: 'any movement more than 3 m from the assigned area without adult permission.' What kind of definition is this, and why is it a good fit?
- A. A function-based definition, because it covers all responses defined by the same effect on the environment, whatever their form.Correct. Function-based definitions include all responses that have the same effect on the environment (here, leaving the area), which suits a response class with many topographies.
- B. A function-based definition, because it was written after a functional analysis confirmed the maintaining reinforcer.Incorrect. 'Function-based' here means the definition is built on the effect of the response. It does not require a completed functional analysis.
- C. A topography-based definition, because the 3-m criterion describes the physical shape of the response.Incorrect. The distance criterion describes an outcome (being away from the area), not the shape or form of the movement.
- D. A topography-based definition, because it lists every specific movement form the client uses.Incorrect. The definition does not list forms. It covers any response that produces the same outcome.
Two RBTs record 'tantrums' for a preschooler. IOA has stayed below 60%. When the BCBA reviews the data, one RBT counted each scream as a separate tantrum, and the other counted a whole crying-and-screaming episode as one tantrum. Which revision would most directly fix the problem?
- A. Have a single RBT collect all data so there are no disagreements between observers.Incorrect. Removing the second observer gets rid of the check on measurement quality, not the source of the error.
- B. Retrain both RBTs on the existing definition and run IOA again next week.Incorrect. The definition itself is ambiguous about what counts as one instance, so retraining on it will not remove the disagreement.
- C. Switch to whole-interval recording so the RBTs no longer have to agree on counts.Incorrect. Changing the procedure hides the problem but leaves the definition unclear. Observers would still disagree about when the behavior is occurring.
- D. Add onset and offset criteria, e.g., 'begins with crying, screaming, or flopping; ends after 30 consecutive seconds with none of these.'Correct. Onset and offset criteria tell observers when an episode starts and ends. That fixes the counting-unit disagreement behind the low IOA.