C.4: Measure temporal dimensions of behavior (e.g., duration, latency, interresponse time).
Free practice questions for this part of the BCBA, with an explanation for every option.
A teacher reports that a student 'takes forever to get started' after being told to begin independent work. Which measure most directly captures this concern?
- A. RateIncorrect. Rate is how often a behavior occurs per unit of time, which does not address delay in starting.
- B. LatencyCorrect. Latency is the time from the onset of a stimulus (the instruction) to the start of the response.
- C. Interresponse timeIncorrect. IRT is the time between two responses, not the time between an instruction and a response.
- D. DurationIncorrect. Duration measures how long the student works once started, not how long it takes to start.
A feeding team is worried that a client eats so fast he is at risk of choking. The goal is to increase the pause between bites. Which measurement should the BCBA use?
- A. Interresponse time between the end of one bite and the start of the nextCorrect. IRT measures the time between successive responses, which is exactly what the team wants to increase.
- B. Latency from food presentation to the first biteIncorrect. Latency to the first bite captures only the start of the meal, not the pacing between bites.
- C. Number of bites per mealIncorrect. Count of bites depends on portion size and does not measure pacing.
- D. Total duration of the mealIncorrect. Meal duration could change for many reasons, such as portion size, and does not directly show spacing between bites.
During a 50-minute observation, a client has three episodes of crying lasting 2, 5, and 8 minutes. What percentage of the session did the client spend crying?
- A. 10%Incorrect. This uses the mean duration per occurrence (5 min) instead of total duration.
- B. 30%Correct. Total duration is 2 + 5 + 8 = 15 minutes, and 15/50 = 30% of the session.
- C. 16%Incorrect. This uses only the longest episode (8 min).
- D. 6%Incorrect. This divides the number of episodes (3) by 50 and confuses count with duration.